See PHI466. Ref T13108. Somewhat recently, new rules were added so that "Resigning" from a revision takes you off the default recipient list, even if you're still a member of a project or package that is still a reviewer or subscriber.
However, these rules don't currently apply to the similar expansion which occurs in notifications. If you resign from a revision you may still get some notifications (just not email) if a package or project you're a member of is a reviewer or subscriber.
(Possibly these should eventually share more code, but just get things working for now.)