According to my analysis, the main reason is the deficiency of server capacity . You might have noticed whenever you create a new account you get bot lobby and bots become less as you rank high . This is not the case as new accounts on emulators get match with royal pass players . I dont deny there are no bots but they are less . the number of bots depend on the server capacity as they are controlled by the server . Also playing a match takes up space in their server and since server capacity for emulator player is less ,there are less bots and more real people . That is the reason why you have more players waiting to play than scarcity of players . As for the third party emulator lobby , i think Tencent Deliberately increases the match making time .
if you use vpn to netherlands in Asia server , you get faster matchmaking(on gameloop its close to mobile sometimes)
but it has really high ping.