Henchmen that could beat their leader, but don't because they respect/worship them
Captain Ginyu - Dragon Ball Z: he could switch bodies with Frieza, but he respects him as a leader.
Ebony Maw - MCU: his telekinesis could probably make short work of Thanos, but why would he? he seems to agree with his goal.
Enrico Pucci - JoJo's Bizarre Adventure: Dio asks Pucci if he will betray him one day. Pucci assures him that he would never do that, because he basically worships him.