that video is technically is film grain. Compression artefact would look more like like this.

For identity verification, you can just do a simple key signing, just like how Nostr does it.

Each user will generate a public-private key pair on their own device and has all their posts (and edit/delete requests) signed using their key.

If someone wants to delete or edit their post, the site can just verify that the request is signed with the same key.

There’s still issue of who’s going to store the user’s follows, etc. but I think we can find a way to workaround it.