That’s what all the section 230 hubbub was about a few years ago.

230.c.1: No provider or user of an interactive computer service shall be treated as the publisher or speaker of any information provided by another information content provider.

As long as they are “dumb pipes” they have no liability. When companies started to “moderate” content that was unaligned with a particular political persuasion, the other side claimed they were no longer dumb, but now editors.

AFAICT, any content filtering that is done is to avoid civil suits and provide the appearance of being helpful to society (or at least not fostering the criminal underworld).

If it is text, am I not allowed to use Google Docs to write my erotic Harry Potter fan fiction?