oh anon it's always been like this with genshin and hsr. it was doomed from the start :')

as for why hoyo specifically, i have a 6 point theory on how this came to be ahahaHA...
1) genshin launched in sept 2020, aka during covid lockdown, aka everyone was cooped up at home and stuck with going online for their social needs
2) it's a lot of people's first fandom
3) it's a lot of people's first gacha game
4) it's a lot of people's first in-depth exposure to east asian media and chinese media specifically
5) the fanbase skews younger
6) it started on twitter. enough said.

the proship/anti nonsense and other trends in fandom behaviors had been going on for a few years at that point (coughs in voltron) but genshin really catapulted fandom into the mainstream. large numbers of new people were joining who had zero experience with fandom before, especially younger people, and bc of the way twitter is, they didn't get the same exposure to previous fandom norms about like shipping or interacting with other fans, etc. and now we have the worst toxic cesspit of a fandom you will ever encounter.

i started playing genshin dec 2020, 3 months after launch, and the fandom already had a Reputation by that point. and honestly genshin is patient zero much like voltron is, in that any and all hoyoverse titles going forward will become equally bad if not worse because people keep jumping ship from game to game.

and yeah, it's really unfortunate. despite hoyo's issues with character design and the inherent predatory nature of a gacha system, they still do make genuinely good games and people enjoy them for a reason. i still love hsr dearly, but i just can't deal with the fans anymore.