I worked as a personal trainer when I was in my early 20s. It had its moments but it's a tough way to make a living. Success comes from salesmanship first, not from experience/knowledge. The hours are shitty, as early mornings & late nights are when most people are available to train. And you'll constantly have to keep "working" the gym to get more clients. The grind never stops.
Most of the people that share your passion for training will just look online for guidance, so you're left with bored housewives and old men--and dont get me started on the bored housewives. They will tell you the most inane, boring stories and you'll have no choice but to feign interest for fear of losing a client. Truthfully, I feel like most people that keep paying for personal training are just lonely and want to have someone to talk to. Nothing wrong with that but I hated listening to their bullshit.
The employment benefits at most gyms are slim, and PTO is pretty much unheard of. So if you get the flu that could leave you without pay for 7+ days. Nevermind taking a vacation. And god forbid you should hurt yourself in a manner that leaves you unable to train for a few months .. that could bankrupt you.
Who knows, Wiggs might be a pretty good PT. I wish him all the success in the world. But I suspect personal training may not be everything that he's imagining it to be.