Request: Provide an official way to *deprecate* a crate. NOT yank. Yank is stupid

I think this should work like "last seen online" status in messenging apps: some people would like to share this, others would find it annoying. In consequence, the crate author could opt in to setting such status information on their crates, but they shouldn't be forced. The opt-in could be the same as the first time you press a "this is still maintained" button on a particular crate. (And you should be able to change your mind and opt out again later.)

Email reminders should be a separate opt-in; I believe it's only acceptable to send each crate author an email unmasked for once (once per person not per crate), the first time one of their crates (that they have opted in to share a status in the first place, as described above) is about to become considered "old".

That email can then contain a section like "This is a one-time demonstration of the crate grace window notification feature. Click here if you do want to receive this kind of email again in the future."

I believe the email opt-in should be per-user, whereas the setting of whether to share any status information should be per-crate.