I say good for users, but that entirely depends on the userbase.
For example, _if_ HN didn't exist as it does now (free) and was paid only, I wouldn't mind paying as its the best "social network" I know of. Problem is, would it ever get to this point if it were paid only? Also seems like any user that would pay, would pay to reach an audience... of non-paying users...
Either way, I don't see a world where this actually works out, but god speed I guess.
Of course, that's probably why he's so eager to hoover up photo IDs and CC info - by continuing a passive account on the platform you've totally given your explicit informed consent to be charged whatever Lord Xoldemort thinks his platform is worth that month...