On the one hand, Change.org petitions are essentially worthless. On the other, it takes like 2 minutes, may as well. On the third hand, as Corbin said (hey Corbin!) call the payment processors. Supposedly this happened because 1000 people called and bitched to them and said sexy things were VERY SCARY and HURT WOMEN (even though women are some of the most horny, degenerate, holy shit porn lovers (and creators) out there). Probably this is just VISA/Mastercard getting an excuse for censorship they wanted to do anyway. but let's see what happens if 1000 people call them and tell them to stop censoring media. Or 10,000. Or 100,000. I supposedly have 4k followers here, and I'm just one rinky dink game creator. Itch just nuked north of TWENTY THOUSAND NSFW games off the platform. Even one caller per game would be a bit noticeable.
If you do, don't be rude to the customer service rep though. They have as much culpability and control over this situation as me (0%). Try to escalate to someone higher up, be clear about the complaint, and try to frame it in broad, non-cringe terms (censorship of artistic expression in general). Stress that the same group wanted to suppress mainstream games like Beyond Two Souls, and basically anything with attractive women in it, no matter how tame.