Na they would just create 1000's of personalities. Maybe by IP Address and time with personalities would work or even better stop ranking by it at all.
I would say having a group of trusted reviewers would be the best way to handle that. Nothing is a good substitute for trusted content curators.
That's a false dichotomy. The choice is not between tie your identity to everything or Chinese rating farms (nice work invoking the scary Chinese other as some specter that is ruining our app processes by the way - remember when the Japanese were ruining everything in the 80s?). There is enormous room for improvement in app rating procedures and process. Saying the only choice we have is what you consider the lesser or two evils based on the current state of the current system is almost laughably short sighted.
Do you want to sort your apps by the the rank and reviews of chinese laborors? Or do you want it to prioritize ratings by people you actually know?
Personalization is really the only way to nuke the arms race that is fraud/spam detection and crowd-sourced data.
There is no perfect answer. Just more abstract games to play.