I'm not sure I understand. This is talking about Cargo metadata download improvements. You still download individual packages regardless of receiving a copy of the entire registry, so privacy hasn't materially changed either way.
If knowing you use a crate is too much, then running your own registry with a mirror of packages seems like all you could do.
If knowing you use a crate is too much, then running your own registry with a mirror of packages seems like all you could do.