Trust of federated servers isn’t the issue. We already trust federated servers to publish the text we wrote and not some alternative version the owner wanted us to say.
The problem is instance owners don’t even have the option to obey deletion requests. They want to help delete your content but they cannot.
The whole “what’s the point of building it if there’s a possibility one dude doesn’t obey the request” is whataboutism.
Fantastic recommendation, will look into these! Never heard of OvvO.