+1.

however, they have answered in discord that they are afraid that separated queues will make it harder to find 8 players to play and it will lead to much longer searching.

yeah, it would. but wouldn't it be better for a player to wait a bit longer and play the mode he or she wants? imo, it's far better than dropping a map you don't want to play, leaving you with ban and other players with bot. when player doesn't care, he or she could still search as it is now.