Bill Zebub
“It’s probably Matt Mercer’s fault.”
Clearly this approach has to have limits, though. If a monster has, say, a fear aura, as a player it is your agreement to acknowledge it and have your character act within those bounds if they are hit by it. You can't (within agreeable play) go "nah, I'm not terrified, so my character doesn't take that penalty". That's incoherent with the nature of the game. An absurd example would be saying "well, I know that I don't die in real life because my character took damage, so it's pretend and I ignore it". So why does a skill-based rule in the same book as fear auras and hp get to be vetoed?
Of course, if Intimidate is not a thing that exists as a general rule for NPCs or an ability of the orc, the answer to the question is plainly no. So within many ststems, the skill-centric reading here is irrelevant. However, if that was a rule that existed, the player is expected to play their character within that "contract".
"Because magic."
If there is a rule in the game that overrides the basic premise that players make their own decisions, it needs to be clearly defined. A "fear" spell (or aura) must have such a definition. "The affected character must move directly away..." etc. etc.
The Intimidation skill has no such definition. I would be totally ok with a character class or monster having an ability called "Intimidation" that defined how it works (even if non-magical). I'm not ok with a player or GM announcing, "I use Intimidation" and expecting it be magic mind control.
As for players saying they control their character's thoughts, and "I'm not frightened" that's fine. But your body is going to be moving in a line directly away from the caster, and your rolls are going to have Disadvantage (or whatever the effects are), because that's what the rules explicitly say.

