My point is that we can't rely on the message to the member that is sent after the spam marking.
I wasn't arguing against your suggestion on that grounds, merely addressing your broad overstatement of facts, lest someone have the impression that the notice seldom or never gets through to the member.
Providing the Owners with the appropriate and unique automatic rejoin link would all us the option to alert the (ex)subscriber if we were so inclined.
You don't need the link to simply alert them, as you and J already do.
I do think there's a technical problem with your suggestion in terms of assuring that only the member in question uses the link. Absent that assurance Mark may as well give owners a control to re-instate the member unilaterally. But that's a decision for Mark to make.
In the last month we had 4 dropped via spam and none were recovered
In my groups (not counting GMF) I believe I'm 2 for 2 recovered on their own, with no prompting or instruction from me. But that's way too small a sample to be meaningful.