Bill Zebub
“It’s probably Matt Mercer’s fault.”
No, see my reply above.
There is nothing 'adversarial DM' about it. I trust my players to play their character accordingly, and to not metagame. I'm not forcing them to act in a certain way, just informing them that their PC finds the statement by the NPC to be (very Persuasive, Truthful, or Scary) depending on the social skill used, and then trusting them to play their character accordingly.
Just like I do as DM when they use their social skills on my NPCs.
Its a question of mutual trust. It's quite the opposite of the players and DM being 'adversarial' towards each other.
Sure, if everybody is on board with the same strict definition of roleplaying. But in that case this discussion is moot.
This debate really only applies where different participants have different notions of how the game works. If a player disagrees with you about some of your preferences (which are valid but not intrinsic to the game) then you can't really say it's a matter of trust, or that you're not forcing them.