In other words, they just need to shrink the rating pool size or increase the predetermined numbers for winning/losing, and reduce the amount of rating ranges in the matchmaking for the queue to go faster even with fewer people.
The rating pool size and the speed of the matchmaking queue depends not on the amount of players per se. What decides it is the metrics in correlation to the player pool. Doesn’t matter if the player pool is large or small, if the metrics aren’t optimized for it then it’ll still go slower.
Also, average wait times makes it take slightly longer for everyone in order to prevent outlier events, and the server configuration for hosting it can have its own internal queues too, which would then also affect queue times.
This illusion that queue times directly correlates to the amount of players is preposterous. The only real effect of more players is that the skill differences in the matchups becomes more equal on average. That’s all.