I do not know the full story behind this, but what you say sounds very worrying. As you say, criticism should always be allowed and the fact that these accounts have downvoted a critical post is a huge red flag.
I don't want to put in the effort just to be downvoted by whales who don't like my content.
I'm not in the "hentai" bubble at all, but I don't see any problems with your posts? Maybe it is something silly? Is it possible that you get downvoted because you upvote yourself? Maybe that's something people here don't like at all? I don't know as I'm new here too.
If you plan to put your account on ice please contact me, maybe you could delegate your HP then 😅