I have no idea how this was possible until the Steam purge, but apparenthy that's not new at all and this is the root issues for other bans on other plateforms (Patreon, possibly Tumblr apparently, OF etc...). Also, no censorship is good. Banning sexual content (on a site that has a tag and filter system on top of that) is stupid and ALWAYS a slippery slope into censoring everything and the destruction of media and culture. Not the first time in history this has happened, and it's always under the guise of "protect women and the children" but look into the people pushing for censorship and you see they are full blown facist and biggots. They don't care about the children nor women.
As a trans man, I can assure you their end goal is to erase queer content and anything they dislike. Banning nsfw is an easy way to do so, they just have to push laws to label queer people as "indicent" or "porn" and boom now we also get banend from being represented or even posting anything.
Edit : Apparently some non erotic queer and horror games also got nuked on itch, according to people on the itch.io Discord server. So that last part is already in motion.