Destinys multiplayer isn't competetive and without a proper ranking system there is 0 reason to listen to little kids on there mic.

I don't play much crucible but have this exact problem with POE where I think it's essential to have a mic. I don't understand why players don't use a mic when it's needed in these circumstances !

No

There's a secondary problem in play. Even if you are running solo with a mic on, any fireteams on your team are in private chat. The easiest and best fix to all Destiny's mm issues would simply be hosted game lobbies like Gears of War. Hosts could set matches to private for friends only or open spots for mm, select game type, map, etc. Host can also kick, so someone won't use a mic and it bothers you? Boot them. Non-hosts could brows groups or just queue for first available of a game type. Solves the issue of no private crucible. Solves the issue of raid mm. Obviously IB and ToO type events would remain unchanged with everyone queueing.