If you happen to be an american, this is probably the one chance to stop these companies from pushing rules on sites like E621, Steam, Itch and a lot of others as they aim to give full stop to the nonsense of them dictating what you can spend money on. If it passes no banking or cash handling business could ever dictate if your site gets ad money or not while they host furry content or anything that they dislike.
https://www.govtrack.us/congress/bills/119/hr987/text
https://www.congress.gov/bill/119th-congress/senate-bill/401/all-info
Please if you live there, try your best at stopping the madness while we still can and pester your politicians in passing the bill.
Edit: Incase you want to support this or in general just oppose what the payment processors are doing but have no idea how, heres a link to a compilation of information, links and ways to help which almost everyone can do:
Edit 2: Additional useful links by TheGreatWolfgang:
https://chng.it/cRSvHKsbtB - Change.org petition to MasterCard, Visa & Activist Groups.
https://stopcollectiveshout.com/ - General resource site, including what this is all about and what you can do about it.
https://www.reddit.com/r/itchio/comments/1m83s71/things_you_can_do_to_counteract_payment/ - Another resource link.
https://www.congress.gov/bill/119th-congress/house-bill/987 - Another house bill to support.
https://www.congress.gov/bill/118th-congress/house-bill/2743 - Another house bill to support.
Updated