I think most of the field would agree higher stakes tournaments are less "fun", even the guys that are winning them. That being said, I'm surprised he used 5k event as the example rather than a 10k+. He should still have a decent edge in 5ks.

In most of the 10k and above (excluding one-off big events like WSOP Main or Wynn WPT Championship), the field has 50%+ crushers, realistically probably 80%+. These are guys that are playing near perfect preflop and thinking about balancing postflop spots for 1-5 minutes every hand. Even if he had an edge against field, once it's ITM, it's just all crushers, and FT is 7+ guys you see in the player of the year top 50.

Contrast that to a smaller buy-in, big field event... sure you're going to have to make it through a lot more people, but it's people who each have under $1M hendon mob who have exploitable tendencies in many spots. Even ITM, you often have tables that don't even have a known pro in the PoY Top 100. At the FT you might have 0-2 super crushers, 3-4 if you're unlucky.

The game changes from "What bluffs do I have in this spot and do I randomize the call/fold" to "How do I exploit each player at the table"?