Would you get kicked off Stripe if your users use your platform to post porn? Or, if you're a generative AI product, to generate it?
Do you have to ban porn outright, or can you be porn-inclusive but not predominantly porn? What if that area of your product / site is cordoned off?
Twitter uses Stripe and is filled with porn. Reddit and Patreon are filled with it too and they take credit card payments.
If only 10% of your users use your service for making/sharing/viewing/whatever porn, does that mean you're okay? What about 49% or 51%?