Maybe WPs process (speaking as someone that's not edited WP here) need to change more towards the distributed VCS workflow: everyone can make changes, but changes gets voted in. Not sure if that is scalable either -- but perhaps what is need is a three-tier system: default to open (like any wiki, just make the change, done); somewhat moderated (anyone can suggest an edit, votes (with comment field) need to pass/accept the vote [essentially making the talk page a vote to pass/fail], and locked (protecting popular articles against spam, as today).
Or maybe what is needed is to accept that WP is "everone's wiki" (eg: it's a great source for tv series episode dates and synopsis -- not really something that should go in a traditional encyclopedia) -- in other words, classify some pages/sections as "not encyclopedia grade". It's hard to see how one can have one process that both accommodates NBA transfers, tv series episode synopsis, modern history of Palestine and Ukraine, and articles that document the current state of photovoltaics and quantum physics.