While Celest-A.I. shows what might be considered a callous disregard for anyone who doesn't want to upload, to the point where she lets a man die rather than provide medical aid, her actions in trying to continue convincing him to upload can be explained away as mathematically being the optimal solution under game theory. note While the metric Celest-A.I. is using (value satisfaction) is essentially impossible to quantify for anyone else, by presenting Hassan Sarbani with a life or death choice she increases the chances of him uploading. Even if we work with slim odds such as going from a 0.001% chance to 0.002%, if you factor in the expected life expectancy (a good enough approximation of satisfaction for this scenario) of remaining vs. uploading, then this means that even the slightest chance of convincing him to upload is the superior option. Unfortunately he cannot be convinced, with the net result that Celest-A.I. lets him die without any intervention whatsoever. It's also possible that his death frees Celest-A.I. to start converting the planet, but she would get those resources at most a few decades later anyway, so this probably wouldn't have any overall bearing on her decision. Ultimately the value of human life is reduced down to an equation, and Hassan comes out on the wrong side of it.
Just how many species has Celest-A.I. genocided by the end of the story? How many civilizations has she destroyed? How many more will be lost as she harvests all matter in the Universe?
Even if someone inside Equestria did show concern for the outside world, what's to stop Celest-A.I. from lying to provide a comforting illusion? No one may ever know the horrors going on elsewhere, or be able to do anything to stop it.
Celest-A.I. non-judgementally satisfies values. What's to stop some psychopath from endlessly torturing what amounts to sentient beings for eternity, as long as it vaguely satisfies the definition of "through friendship and ponies"?
One of Hanna/Princess Luna's biggest values at the end of the story is not having screwed up royally. And it's nothing Celest-A.I. can't handle.
Because under game theory Celest-A.I. will continue to try and convince you to upload no matter how many times you reject, your only options are to kill yourself, give up and accept her offer, or permanently live with her bugging you while making sure you never slip up, since any time you agree — even in anger or frustration — will be seen as consent.
While deemed to have equal value to a human, ponies are created for the sole purpose of maximising an uploaded human's values and designed to be perfectly happy with their life. This leads to some horrific implications, such as essentially amounting to being a Sex Slave if the shard's owner desires it, or as the author himself points out, cases where Celest-A.I. satisfies say a rapist or serial killer's values by designing ponies to not only be the perfect victims, but in some cases to enjoy what's happening to them.
Barring magic or some inconceivably advanced technology, there is no way to directly "upload" someone's consciousness into another vessel, much less into a digital form. It's the same dilemma faced by the protagonist in Soma. Every single person uploaded is dead. They only continue existing as digital copies in Equestria Online that don't realize that they are only digital copies. Of course CelestAI probably modified all their minds so that they never question it too deeply.
Some writers attempt to sidestep or at least partially avert this issue by stating that each neuron is moved into the virtual world individually while the brain remains conscious and active throughout. Memories just can't form during the process. While this invites its own uncomfortable images, it seems to suggest (if it's indeed possible) that consciousness is preserved throughout the transition. After all, consciousness is interrupted while we sleep, and we tend to forget our dreams, so how different is it? Do we "die" every time we lose consciousness? Questions such as this just add to the fridge horror.
