Outside of RP realms, there is no more "community" in WoW. 90% of the players that I come across in the game world are highly selfish.
For most of us, true community lies within your guild.
While I am personally a fan of PL, I don't think it is fair to limit choice for people who may want to enjoy the game differently from myself. We had multiple ways to loot for years and outside of a few assholes, everyone did just fine with them. I really don't think PL belongs at the Heroic or Mythic level.
Not a fan of Master Loot? The solution is easy. Don't PuG with the ones that are using it. There are always plenty of PL groups to choose from.