Ehhh... I think he's wrong. Right about the ideology over gameplay part but wrong about why indie devs washout.

They don't "wash out" they shot their load and got out. Sure, you have your "stars" who can continue to produce hit after hit but there's very few of them in relation to the vast number of people who attempt it. How many book authors out there only have ONE book? Lots. Same with bands and performers, you get your one success out there but don't have the creative oomph to assemble another one or maybe you did what you wanted to do and move onto something else.

Now those who want careers in the field go for the big or small corps to try to have some stability and that's true of other creative fields as well.