Eh, I have no love for vtubers and I don't even watch twitch streams, I have no patience for them, yet I kinda care because:

1. Amazon is using its power to fuck part of its content creators while leaving a larger bunch completely unscathed with pointless double standards. Just shrugging at it makes them more likely to further ignore feedback.
2. Amazon's moderation is a piece of shit, akin to Youtube. Streamers that follow the rules can get banned because of loose interpretation of certain rules, while blatant disregard will remain because haha fuck you. Thus, application of the new rule will be inconsistent at best.
3. Amazon doesn't actually care about the whole "sexuality" aspect, otherwise they'd go after the many borderline porno streamers.

But most importantly, I care because it's a giant corporation fucking the people that help it make money.