It sucks but what can itch.io do? If they allow nsfw games to turn a profit they risk their their entire payment providers pulling the plug, then everyone gets screwed, NSFW and SFW devs, nsfw my be saved later but only if there's a platform to be saved on is still there.
It's aggravating to be sure, trust me i sympathize as another nsfw dev, but you can see itch's side too, if they allow it they get their entire business screwed, there's no winning sadly.
If nothing else itch.io still allows free(No Payment) nsfw games, which is great for getting your stuff seen which is something. Most of us are just uploading free "no payment" and embedding a button in our games that takes peeps to our kofi, patreon, etc if they wanna support us, it works, not exactly practical but it works.
Just try and make the best of a sad situation until payment processors stop being butts, until then all we can really do it hope and pray sadly, :o