I don't want to see furry smut either, but for fucks sake I think that everyone should be able to pay money to their favorite furry smut artists if they want to. Credit card processors should only be allowed to refuse transactions if they actively break a law.
Other than that though, I think platforms should be free to ban smut if they want. I’ve abandoned several sites over time because they became inundated with cartoon smut, which I am not interested in.
Would a good filtering options, defaulted to SFW be enough for you? That it what I think should be the norm for content hosting platforms.
While I agree on principle, I also see the dangers of platforms caving before Evangelical pressure campaigns. And once this is established, the threshold to cross from "ban furry smut" to "ban anything even smelling like LGBT" is much much thinner. My personal patience with and trust in platforms to behave sanely is all but gone.