If you use the server browser to find a community server that offers you the game mode and maps you want, with a ping you like (or easily create your own if you can't find it already existing), you will not need to rely on matchmaking, you won't be switched to a different lobby every round, you won't play attacker or defender over and over or the same maps over and over in a random way, and clan members can easily find the same server, join, and never be disbanded regardless of what party they are in. If you do it, and everyone else with the same complaints does it, you will see enough people in the community servers to never complain that the only reason you don't is because the servers are empty and they are impossible to get started.
Everyone who complains about matchmaking just needs to stop using matchmaking.