Bill Zebub
“It’s probably Matt Mercer’s fault.”
Do you react similarly to combat?
After all, the DM is telling you that you have lost HP. You have lost conciousness. Hell, you might even be dead, with zero input from you. Do you have a similar level of "I don't think Mr. B would really do that?"
I can only answer for myself, but for me there is a clear distinction, and a hard boundary, between "You get hit by a sword and you bleed" and "You get hit by a persuasive argument and you believe." One affects the body, the other affects the mind, and what goes on in my character's mind is exclusively mine to decide.
The only exception is magic (or psionics or whatever).
Even systems that have mechanics that affect the mind (such as Sanity) should still respect this boundary. It's fine to impose penalties or restrictions ("you can't take any actions until your Sanity score is above X" or whatever), but thoughts and decisions still belong to the player, and flavorful play should be incentivized, not dictated. A player who refuses to play along with the game in this regard is just another flavor of jerk, and the solution to jerks is to not play with jerks, not come up with more rules.