Its good advice. In tech i think they call it doing things that dont scale. That way, the only thing stopping you from making X amount of money is simply sheer volume, which is moreso under your control than luck or having a million dollar talent - hes saying all you need is a 10 dollar talent. Which is true
I think people arent so much wanting to know how to make a million dollars but how do they make a million dollars before they get too old to enjoy it
If you plan on making a million by 50 then all you need to do is follow his advice. If you want to be a millionaire by 25, you probably need something else