This would solve classes of issues with the npm ecosystem (many of which remind me of trying to register a domain name) like name-squatting, trying to think up a marketable-but-untaken name, and ownership transfer.

OP claimed a bunch of sweet dictionary words (concat, iframe, door, bud, alert, map) and new owners are now claiming them and it's a security disaster. But it'd be a lot less interesting if they unpublished "azer/map", "azer/alert", "azer/iframe", etc. and new owners republished under their own names.

Elm packages got this right: http://package.elm-lang.org/