Some far-right group pressured Steam and Itch.io into removing content by lobbying the payment processors. I'd guess that it was not so much due to those particular a*holes, but because of the general political situation in the US.
Nonetheless, let us stand together against censorship.
https://www.rockpapershotgun.com/itchio-apologise-for-frustration-and-confusion-after-delisting-thousands-of-nsfw-projects
Petition: https://www.change.org/p/tell-mastercard-visa-activist-groups-stop-controlling-what-we-can-watch-read-or-play
Contact information of the payment processors:
Mastercard
Phone (US): 1-800-627-8372
US option selection for operator: 1, 1, 2, 2, 2, 1
Phone (outside US): 1-636-722-7111
Email: customer_support@mastercard.com
Online form: https://www.mastercard.com/us/en/personal/get-support/ask-mastercard.html
Visa
Phone (US): 1-800-847-2911
US option selection for operator: 1, 1, 2 or 1, 1, 3
Non-US phone numbers: https://usa.visa.com/contact-us.html
Email: askvisa@visa.com
Online form: https://usa.visa.com/Forms/contact-us-form.html
Paypal
Phone (US): 1-888-221-1161
Phone (outside US): 1-402-935-2050
Hours: 6am - 6pm PT
Online form: https://www.paypal.com/uk/cshelp/complaints