itch.io

Itch.io isn't obligated to offer anyone a platform; no one has any inherent right to upload whatever content they want onto itch.io. I interpret the intended message to refer to ability, I just tend to be easily irritated when ideas of "rights" and "censorship" are mentioned erroneously.

This isn't so much the fault of itch.io as much as it is payment processors and the lobbyists pressuring them to punish entities for transacting in a "problematic" manner. If anything, this is where rights and censorship should be a concern. If an artist is commissioned by a customer to draw pornographic content, and the two exchange product and payment and respect each other throughout the transaction, there is no issue and it's not the intermediaries' business so long as it isn't actively breaking any moral or legal boundary.
The difference between itch.io deciding something is not acceptable to host, and a payment processor blocking transactions they deem unacceptable, is the fact that unlike itch.io, said payment processors have effectively monopolized all ability to digitally exchange value, whereas you have many other options for distributing your art besides itch.io; when they dictate what transactions are considered acceptable, they in essence can make any transactions they don't like "illegal" despite not technically having the authority to enforce any law.
Capitalism fucking sucks, reason #99999...

And no, cryptocurrency is not a solution and anyone attempting to entertain the idea of using it should be laughed out of the room.