Here you go OP
https://us.forums.blizzard.com/en/wow/t/ok-we-tried-it-for-a-tier-no-master-loot-sucks/25578
It’s been discussed to death. There’s literally zero reason to not bring it back as an option, but unfortunately (or fortunately depending on where you stand) Blizzard disagrees.
Oh and to be clear… no I don’t think they should remove PL, but yes they should bring back ML for guild only groups as an option.