Why no comp mystery hero?

Mystery hero quickplay is clearly very popular, having instant queues.
And the same was with comp.
But let me throw a thought here or lets call it a theory.

OW2 lose smurfs and streamers when having comp mystery heroes. Simply because they can’t choose the bully heroes they want.
Fewer smurfs and streamers = less PR and revenue.

I mean, why would you otherwise remove something that is clearly popular?