I would hav thought stuff like Lemmy would have configurations to eg.: not allow to upload images locally, only hotlink.

Anyway, an alternative is "zero knowledge" storage, where you don't know what you are storing (hence, you can't "choose" what to host or not host either). Another alternative is disjoint storage, where two different servers store different halves of a file (eg.: an Odd Bytes server and an Even Bytes server), but this means now it's necessary to hit more servers to recover a file.

But the sensible thing to do IMO is to apply "common carrier" concept. The water distribution company is not, to my knowledge, held liable when something happens like you fill a bucket of water and share it with someone else.

There's gotta be some kind of limited liability for this kind of thing. I mean, banks wouldn't be liable if someone put csam in a safe deposit box or (assuming they don't x-ray packages) UPS shipping csam in a sealed package. I think there just needs to be reasonable safeguards against it but I don't know if any of that is built into the software.

Probably arrange it such that not one person/server knows what the stored bytes are. There can be a server where the bytes/blocks get reconstructed where one can check for the bad stuff.

Maybe nobody keeps a complete file? That way no one machine can keep a complete copy of anything let alone access it if it was stored in a single chunk of storage cryptographically? There’s already so much risk for hosts here not sure there’s a way to be safer without invasive technologies.

Depending on if you have DMCA safe harbor protection