Back when I played Destiny a lot, I once joined a pickup group for the weekly raid. Having done it multiple times at that point meant nothing. If your team sucked balls, you could kiss the completion goodbye. And yeah, that team sucked. Mostly because there were two guys with different strategies, and they were both convinced their way was the best, so they just did it without telling us what they were doing.
The only one who actually did do great, had no mic. After calling it quits (after wasting 4 hours), he sent me a friend request.
Turned out the dude was deaf. I played often with the guy. No mics. No talking. Just dancing, or jumping. I'd send him an invite, asking for help with a particular hard weekly mission, and he'd join, and whoop ass. He adapted to any strategy we used flawlessly. He joined a clan, that managed to clear the raid in Destiny 2, with a team consisting of only deaf people.
In case you don't know, the final boss in any Destiny raid usually requires some form of timing among players, and sometimes directions given by one player to the rest. They did it using specific combinations of emotes to indicate certain keywords, or countdowns. I watched a bit of their stream. It's remarkable.