The Reveal in Chapter 36 casts everything the class did — and the consequences they suffered — in a whole new light. They weren't just being misled by Lila; Alya knew the truth the whole time, but jumped at the chance to turn the whole class against Marinette... all because she was envious of her 'bestie's' success and feared that she might leave her behind. So she aimed to break her spirit and 'cut her down' just so she would 'stay with her'.
Kim and Alix took the bullying to physical levels, even delivering a No-Holds-Barred Beatdown to Marinette in the middle of the park. Alya witnessed this incident - and unlike Lila, didn't suffer so much as a flicker of doubt over how far things were going.
Everyone involved in the bullying has had their reputations ruined, casting their futures in serious doubt. And all of this can be traced back towards Alya's envy of Marinette and wanting to force her back into being an Extreme Doormat who would never leave her.
Also, with The Reveal, it makes it clear that Alya knew that her friends were never going to get anything out of Lila (especially Kim and Alix, who had turned to violence in hopes of scoring some sports scholarships), yet she had encouraged them all to bully Marinette. It actually makes her closer to the canon!Lila, as she had strung them along for her own goal of keeping Marinette to herself and knew that they weren’t going to get rewarded for it.
Even with her upcoming departure from Paris, Alya better hope that the truth never comes out. Neither her former friends or their families would take the revelation that she manipulated them to that extent or the reason for her using them was to try to keep Marinette in her grip very well.
Worst of all, Nino's Armor-Piercing Question calls into question whether Alya stepped in to defend Marinette against Chloé because it was the right thing to do... or because she wanted to 'play the hero'. Note that she specifically complains that Marinette's successes were making her more confident, implying that she preferred the idea of her 'bestie' being a Shrinking Violet and Extreme Doormat (making her very similiar to Chloé and her dynamic with Sabrina.) completely dependent upon her 'protection'. Alya may well have been a False Friend the whole time.
