Aerion might be a cruel degenerate piece of shyt, but unlike Joffrey he can at least scrap

You can tell all that highlord training paid off, he was giving Dunk the business
I thought that was cool to highlight too. If you grow up in a castle as a royal or son of a lord you get trained by a master-at-arms from the time you're a child to adulthood. Knights and guards give you advice, spar with you, etc. So if you ever face off against some peasant with a sword you're gonna destroy them. Not to mention you'll have access to superior swords and have real armor.
One thing I kinda wished the show mentioned was how Baelor's son wins a bunch of matches at the tournament but he only faces squires, old men, and untrained men-at-arms. Breh basically whoops a bunch of plumbers lol. That's why when Dunk thinks Valarr is going to win the tourney, Egg is like aite I'll take that bet lol.
This is also why if you are really about that life you become a household name. The best knights are like athletes for us. In Westeros people like Jaime Lannister, Barristan Selmy, Arthur Dayne, Dunk, Rhaegar Targaryen, Robert Baratheon, etc are like Michael Jordan or Jerry Rice.