Source Reference: https://www.youtube.com/watch?v=CcpQgKnq6Bc
Comment Reference: https://www.youtube.com/watch?v=CcpQgKnq6Bc&lc=UgzDApUjLPUkzLJMgFx4AaABAg
0:00 Whatever it was, you should never-ever loose your own messages at the very minimum, and ideally not even those messages you've loaded, seen or read before. Furthermore, it should be made very clear what messages are public, and which ones are removed, if deletion by somebody else should be a thing at all (if you host your content yourself in a federated way). At least, one should get notified about such serious changes, otherwise the user would wrongly assume that it is still public/available, and popular sites like YouTube fail miserably with this as they engage in ghost banning, so they can't seriously be considered a publishing platform any more. Why do others have control over deleting or hiding my things, if they don't want it, they should just not include it in their own curated lists of material.
Comment Reference: https://www.youtube.com/watch?v=CcpQgKnq6Bc&lc=UgyfPf_qK98l0MovKSx4AaABAg
2:43 There's "Citizen Four", but it's a restrictively licensed movie production and therefore irrelevant. Not speculation. Those things happen, by the state, companies, groups, individuals, machines.