If they can choose a different client, is it really censorship or could it be curation? Can you say for certain that it would 100% be censorship? Is curation censorship? Should client made for kids allow porn or would curation be the key there? Would that be censorship?

Tough questions. I don't think it is good practice for the client creator to add a shit emoji (funny but not good practice); but I have a hard time seeing that as actual censorship when you can switch clients or even create your own.