I feel like you've missed the point of the comment you're replying to

No, a barbarian is not expected to deadlift IRL. But if a barbarian walked into the middle of a situation and declared he was going to solve it with Athletics, without explaining how he was going to do that, he would be met with blank stares. You need to state intent. "I'll use Athletics" is meaningless. "I'll pile up these boulders into a staircase so we can climb over the wall" is a course of action.

Similarly, "I'll use Persuasion" is meaningless. Worse, are the people who just say "I've got proficiency in all the charisma skills, so I'll just use whatever one's most effective" lol. "I'll use my wit and charm to convince the guard that we have been invited to the castle" is a course of action. "I'll use facts and logic to convince the guard that it is in his best interest to allow us into the castle" is a course of action. I don't care if you're charismatic in real life, but if you can't even summarize what you're trying to say, how is the rest of the game world supposed to respond to it? "I'll Persuade them" is only the first half of a sentence.