I feel like many people simply struggle with media literacy. As in, reading between the lines. They see the surface level cool guy and leave it at that, no further analysis.

People either identify with the irritations Bateman has, or like the movie for its commentary on society and therefore choose Bateman as a symbol of the entire movie.

For the first group, some really want to be able to say "fuck off" more often but aren't able to because of society. They feel like they're close to snapping and seeing someone else act out their shameful desires brings them a lot of enjoyment.

For the second group, they are mostly ironically (sometimes post-ironically) fanboying Bateman. They might think that by drawing attention to the ridiculousness of him getting away with his actions, they are providing commentary on the state of society. In a sense, they'd be calling Christian Bale's acting "based" because of how realistic it is.

Rich and good looking

Bateman is also an extremely metrosexual character.

I heard a radio interview from the author Ellis where he said he'd written American Psycho after getting an unexpected windfall from his first book at a young age. Part of the book is based on his experiences as a closeted gay man in that era of Manhatten.

Perhaps people love a man that they can relate to🤷

IIRC he's supposed to be a satire of stockbrokers from the 80's.

He really does capture what it is like being one of those Wall Street types. Everything from Daddy getting him the job, his total lack of technical and soft skills, his lack of distinct self, and not even the basic virtue of hard work. An entire civilization resources going to maintaining the image of a small select group who statistically would perform better if they didn't show up tomorrow.

They are the royality without the nobility.

A lot of them are 13 year olds that idolize Bateman. It’s relatable to them.