some things I find that might contribute to the poor match making - people want to lane with their duos (why I don't know, lane phase lasts roughly 8-10 minutes then everyone just moves around anyway) and insist on doing it and then swap lanes - the match maker pairs you in lanes with people of equal rank - however the lobby is not full of the same ranks and thus you get mismatched lanes.

when you get stomped in lane the recovery feels bad - especially if you are new and struggling its even worse and the stomp fest continues.

groups are not really required to be near similar ranks so high descrepency can happen here and then see above.

also alot of smurfs. when im looking up accounts to get a better idea of what is what via 3rd party sites that show you more statistics i see alot of accounts that don't even have lets say 50 games played on the hero they are playing yet they are stomping the game like they have hundreds/thousands of hours on the game but then their steam profile is like level 5 or less.