100% my thought based on our past experiences. I will say, "busy" at OBB is still waayyy better then "busy" on a normal park day.
We went late last September on a weekday, and RSR and Guardians both had a 60 minute wait all night (with all three elevators working). That was despite huge lines at the treat trails.
In the final hour, the treat trails had no waits but the big attractions still did.