Yeah that sounds like complete bullshit to me. I know some top quant traders who make high-six/low-seven figure comp consistently at that point in their careers, but they're nowhere near able to retire with a comfortable lifestyle, and that's an extremely biased sample. For every person like them, 100 others fail early on, 10 stick around making a nice but not much higher than Google salary, and 5 have a couple busy high comp years then get pushed out by greedy management, have their edge eaten by competitors, or quit when the markets slow down.
Getting to that level is like making partner in a law firm. You have to do much better than "well" and anyone who gets there would be a fool to retire and likely wouldn't want to anyway due to the personality traits/defects required to get there in the first place.