$queryStats is an aggregation stage that provides the user information about query shapes. Now that an operation could be deprioritized, we could add extra statistics in this stage, that could help us determine in the future what kind of query tend to be de-prioritized, or could be de-prioritized if it is not enabled. Additionally, we could also add total time in the queue and other execution control estatistics (maybe delinquency stats). The purpose of this ticket is to first sync up with the team that implemented the stage to define which statistics would be useful, and add them.