I am a content producer and I hope to eventually make games, someday. Yes, it's tough to monetize. But this sounds more like sour grapes than a substantive piece about the realities of making indie games. The earlier numbers are, at best, incredibly hand-wavy and he essentially admits to making them up whole cloth:
I’d guess 90% of that belongs to maybe a handful, at best 4 people? (I have ZERO idea, this is my guesswork)
It is one thing to infer and have soft figures. It is another to make strong assertions about the entire industry and back them up with numbers pulled out of thin air that don't even qualify as "soft."