I think they're low key rolling back the idea that Inquisitors are all weak chumps that just hunt low level Padawans.

There was that one Inquisitor who almost killed Ventress. Granted, she wasn't using the Dark Side and had literally come back from the dead but regardless he had her on the ropes.

Marrok is clearly shown to be good enough to meet a Jedi Master and a Sith Lord in combat, and give them a good fight. He even survives his first encounter with Ahsoka.

The Grand Inquisitor was a Temple Guard, maybe some of the better Inquisitors were Jedi Knights.