Another important skill for a good GM is to be able to read their players and run the game in a way that makes those players as happy as practical and possible. So if a player doesn't like being told how their character feels is at the table, the GM adjusts their behavior to not do that thing for that player's character's actions. It's harder at conventions and other circumstances where you are exposed to new players more often, but it's not impossible.
I mostly took issue with the assertion that the behavior was a definition of good GMing when it's entirely a player preference thing.