The database table oc_capture_agent_role seems to be supposed to assign roles to capture agents that are allowed to schedule events on that capture agent.
There is, however, no functionality that would ever set values in that table and only a fragment of code that indeed would read values from that table to determine whether a given user may "see" individual capture agents.
Interestingly, the query has the second highest throughput on our cluster:
While the idea itself is sound and might be a way to improve to the current implementation of capture agent access management in the future, there seems not much point to me in having this code that causes tons of database queries without actually being used. And if somebody wants to actually make it useful, just add the code again.