What do I know, I don't run a billion dollar startup. But there's a valuable "necessary but not sufficient" insight to all good advice. The lean startup IS good advice. The best I can do with your argument is "getting out of the building is no longer sufficient".
Sure. But it doesn't make the entire arch of how we got here "wrong". And yes, all companies were started with a few people, a few customers. So that's why there's nothing much here to see for me, other than defeatist sentiment.
Seriously, how do you even realistically approach taking on ASML. They spent decades and billions of (investment) dollars to do insane moonshot research and it paid off. But it also closed off the door behind them.
Entire countries (Russia, China, ...) have been trying to reproduce it. They have not succeeded yet.