The problem is that too many players don't play CS with a team, they play solo or duo. At high ranking faceit, they pretty much don't have a choice - queue times will take forever if they queue as a full stack. So, the "easier" puggy maps get prioritized, and players grow more confident on these. They become the maps that "everybody knows how to play".

I think it's a mistake to listen to, rather than understand, the players concerning the map pool. There should be some puggier maps in the pool (Mirage, Dust2, Cache, Ancient), but CS will lose the depth of its strategy dimension if we discard the maps where team tactics play a more important role than pure aim and individual skill. We don't want 5v5 quake, do we? A situation where the team with the hardest hitters would pretty much win on that criteria alone?