That's entirely fine.

Legally it’s fine to discriminate against some things, yes. Morally, that’s not very clear, it might actually not be entirely fine.

It actually, clearly, is.

No, the general concept of arbitrary censorship by web hosts isn’t fine at all.

This isn't arbitrary and isn't censorship, you moron.

How is it not? A platform deciding on a whim what sort of content can get your hosted site banned? That’s the definition of arbitrary and the definition of censorship.

It’s not government censorship, but it’s censorship nonetheless.

It's not "on a whim", it's clearly and publicly documented. That's not censorship.