History YMMV / ItsAlwaysSunnyInPhiladelphia

** Seasons 15 and 16 have attempted to reverse some of Charlie's {{Flanderization}} by having him play the [[OnlySaneMan voice of reason]] to the other Gang members more often and giving him more DeadpanSnarker moments than usual. He also gets a major story arc revolving around the discovery that his "pen pal" Shelley is actually [[spoiler:his father.]]

** Charlie is very brash, hotheaded, childish, has NoSocialSkills, and is very BookDumb, though he's also quite cunning when he puts his mind to it, to the point where he's often described as a savant. Consequently, a number of audiences interpret him as being autistic or otherwise neurodivergent. [[note]]In their podcast, this was brought up. Charlie Day made the comment that both he and his character are ''probably'' autistic.[[/note]]

** Many fans choose to believe that the flashbacks depicted in "The Gang Buys a Roller Rink" are actually the Gang's [[UnreliableNarrator unreliable memories]] at play given that their characterizations wildly contrast what has already been firmly established in continuity. Specifically, Dennis and Dee, who are portrayed as having been [[UsedToBeASweetKid good-natured and innocent]] until the revelation of Frank's infidelity made Dennis a cynical, sex-crazed sociopath and a severe head injury caused Dee to develop into the temperamental and bitter {{Jerkass}} she is today.

** Charlie is a StalkerWithACrush to the Waitress who keeps saying he will leave her alone but never actually does, was seconds away from torturing a "leprechaun", and is just as sexist as Mac and Dennis. But he's a victim of CSA by his uncle, and no matter how much he tries to deny it, he wrote a whole musical about being in love with his abuser. He was also raped by Dee, and doesn't want to be alone with her after (although he does quarantine with her during the COVID pandemic later on, along with him joining her on her excursion to get ice in "The Gang Solves Global Warming", albeit the promise of free cat food). He also grew up fatherless and never knew who his father was as his mom was a prostitute. When he finally does meet his biological father, he dies a few days later, leading him to have an emotional breakdown over having to carry his corpse up a mountain when he was never there for him growing up, and only finding closure in the fact his death means he doesn't have to wait for him to show up.

** Mac would fall back into base breaking after coming out however, with some fans disliking how he no longer acts like a wannabe badass and has now become an ExtremeDoormat, especially in terms of his relationship with Dennis, who he now has a barely hidden crush on, while he, and the rest of the Gang, constantly state how much they can't stand him. "Mac Finds His Pride" is one if not the most divisive episode of the series due to portraying Mac's struggle with coming to terms with his sexuality and his father rejecting him in a serious light, which some view as jarring and unfitting for a show like ''Sunny''. Some fans, however, argue that Mac's personality change has to due with him no longer having to overcompensate for his masculinity or crave approval from his father, and applaud "Mac Finds His Pride" for the fact it's not played for laughs in a tear jerking yet moving and beautifully choreographed dance scene. Mac's character would get re-railed closer to his older self in Seasons 15 and 16, along with Dennis not acting completely repulsed by him, something many fans appreciated.

** While fans agree that most characters are jerks, Charlie is usually considered the TokenGoodTeammate of the Gang. The truth is that he has done many terrible things like his friends (sometimes with them, sometimes by himself) and tends to get a free pass because he's insane and out of touch with reality.
** To a lesser extent, Mac has also gotten this treatment, especially after coming out of the closet in later seasons. He tends to be viewed more sympathetically than the rest of the Gang (it doesn't help that the Gang ramped up their mockery of him during that time), when in reality, he's also done his fair share of awful things, as well as being misogynistic.

** The Gang's love of Kanye West gets substantially less funny after West came out as an antisemite and Nazi in 2022. Given that even they draw the line at overt racism, that likely put a damper on their appreciation for him.

** The Waitress gets this treatment, too, from just about everyone besides [[StalkerWithACrush Charlie]] (who is, interestingly enough, played by Mary Elizabeth Ellis's real-life husband). Shallow Dennis talks about her as if she were [[AbhorrentAdmirer downright repulsive]], even only giving her one star on the sex tape they made, but she is actually quite pretty. It could be assumed that she's rejected by most men because of her alcoholism and toxic behavior.

** Charlie is a StalkerWithACrush to the Waitress who keeps saying he will leave her alone but never actually does, was seconds away from torturing a "leprechaun", and is just as sexist as Mac and Dennis when he's angry enough. But he's a victim of CSA by his uncle, and no matter how much he tries to deny it, he wrote a whole musical about being in love with his abuser. He was also raped by Dee, and doesn't want to be alone with her after (although he does quarantine with her during the COVID pandemic later on, along with him joining her on her excursion to get ice in "The Gang Solves Global Warming", albeit the promise of free cat food). He also grew up fatherless and never knew who his father was as his mom was a prostitute. When he finally does meet his biological father, he dies a few days later, leading him to have an emotional breakdown over having to carry his corpse up a mountain when he was never there for him growing up, and only finding closure in the fact his death means he doesn't have to wait for him to show up.

** Many fans of color find Dee's characters and the Gang's use of {{Blackface}} and {{Brownface}} hilarious and not offensive at all, specifically because the Gang are idiots whose use of stereotypes is seen as offensive and tasteless InUniverse. Needless to say, fans were displeased when several streaming websites removed these episodes.

** In the episode "Mac and Charlie Write a Movie," a running gag is that Dennis is spending all of his time typing on his phone, which was supposed to be inherently ridiculous. Years later, with the popularization of smart phones, it's a ubiquitous complaint that people spend too much time on their phones.
** "Charlie Catches a Leprechaun" has the Gang's attempt at running a "mobile bar" on Saint Patrick's Day failing because Dennis insists on an online pay system instead of cash, with the joke being that Dennis refuses to accept online pay systems are a novelty and too complex for the average consumer. By TheNewTwenties, mobile pay systems such as Venmo and Apple Pay became mainstream and the most popular payment methods for many consumers, so Dennis insisting on his method would be considered a normal business practice.

* MisaimedFandom: The show has gotten both praise from racists and criticism from activists for its occasional depictions of {{Blackface}} and {{Brownface}} with Dee's acting characters and the Gang's ''Lethal Weapon'' sequels, both of which have led to five episodes of the show being banned/pulled from streaming services. Both sides completely miss the point that, not only are the characters all terrible racists, but the portrayals are depicted as ''offensive'' InUniverse, with bystanders of all races reacting to the acts with horror and anger.

** Along with Dennis' line about having emotions like some fourteen-year-old (the time he was raped), him breaking down so hard when faced with his mother's skeleton gets darker when "Frank vs Russia" makes explicit that Barbara either groomed (at best) or sexually abused him (at worst).

** Charlie's mom Bonnie Kelly. She is terrified of everyday things (she fears dogs will eat her face, and refuses to go to the supermarket because "shopping carts are dangerous"), switches lights on and off three times as well as locking and unlocking doors three times "so Charlie doesn't die". It is implied that it is a new behaviour, as Charlie is surprised by it, but overall it speaks to some sort of anxiety disorder.

* OneTrueThreesome: Dennis/Dee/Mac was very popular in the early days. WordOfGod has confirmed both, saying Dee and Dennis are perfect for each other (and have kissed), while Mac and Dennis are in a romantically codependent relationship that they don't want to admit.

* ReplacementScrappy: Cindy's character, while genuinely necessary to fill Glenn Howerton's absence in the first episode of Season 13, was a deliberate invocation of this trope -- a new character played by a well-known celebrity, made to fill a void yet always feeling somewhat out-of-place. Many viewers who got the joke [[XPacHeat still hated the character regardless]].

** Several people new to this show now recognize [[Creator/LanceBarber Bill Ponderosa]] as the dad in ''Series/YoungSheldon''.