devtrackers.gg
I feel like they shouldn't restrict the parties, but just matchmake based soley on the highest ranked because it is the lower ranks descision to play with the higher rank.
If a Daimond queues with their three Copper friends and you get put on their team, how would you feel about that?
Would the diamond really queue up with three copper friends if they knew they'd run the risk of getting matched against five genuine diamonds, though? I think the amount of diamonds that feel like they can take on five enemy diamonds on their own is extremely low.
If that's the only way they can play with their friends, yes. They also might care a lot less about their rank than you.
Realistically, it isn't a great solution and the potential for trolling is substantial. We have other ideas in the works that we feel address the issue is a better way, but aren't ready to talk about quite yet.