I used to think this was just a cultural shift, now though I'm wondering if it's not something more fundamental. It might be an unavoidable symptom of shifting

I used to think this was just a cultural shift, now though I'm wondering if it's not something more fundamental. It might be an unavoidable symptom of shifting priorities from addition to revision. When I've worked on joint drafts, having many collaborators tackle a blank page is incredible. Our ability to rapidly churn out rough but readable pages is always stronger than I expect. Each new edit, even sentences in broken English, are putting ideas on the page, contributing value, and so more collaborators is almost always for the better. There always comes a turning point during drafting, though, where additional collaborators suddenly become a liability. You always want a few different eyes for editing. But when you have enough collaborators polishing a mostly finished product, it will kill that piece (or add months to drafting). My most optimistic read: maybe this is ok. Polishing is harder, not everyone is good at it. Maybe we should expect more edits to be rejected in articles that are 95% of where they need to be. Pessimistically, though: Maybe each new collaborator just increases the risk of bikeshedding and petty squabbles. A couple bad edits create presumptions in editors, driving them to revert even high quality additions as their heuristic subconsciously shifts from "new stuff useful" to "new stuff harmful." The most stubborn or fanatical will drive out reasonable high quality editors, leading to a quality death spiral. I don't know, it's probably somewhere in between.