Damn who would have thought “people tend to play stronger specs” is apparently nonsense only believed by bad players.
That website you linked, which shows number of games, matches closely with arenamate which shows number of players… both of which show BM and SV substantially more represented than MM in 2v2 and 3v3. I also noticed that out of the 4 possible set of ranged statistics (EU/US and 2v2/3v3) you chose the one that has BM and MM the closest and it’s still a considerable gap 
So there it is: MM is not the strongest one yet that’s the one uninformed players complain about. My entire original point. This happens a lot, you know; I say something factual about PvP and you derail to try to make an argument when it just comes back to what I said in the first place being correct.
Never forget: