so many players tr6 to force murlocs each game, only one wins with it. That’s the issue. Everyone is losing to a single murloc player who gets lucky while often 2-3 others lose trying to force murlocs. This dilutes the murloc winrate.
TLDR blizzard doesn’t see murlocs as a problem because 3 out of 8 players lose with murlocs every game they are available.
meanwhile, one player gets an early megasaur on turn 6 and the game is effectively over for everyone else.