Two mistakes: one, survivorship bias, lots of people spent money on tech that didn't work. And two, the problem isn't that he is spending money, it is that he is spending money on something that continues to show no revenue. The point of spending money is not the technology, it is to get a return of more money later.

I can't think of any technology that required multi-decade spending on this scale before revenue, fusion? If something needs multi-decade spending, it is either a scam or uninvestable.

VR had 50 years of R&D before they hit markets. Computers had 50 years of R&D before they hit markets. What exactly are you talking about? You are discounting the largest buyer in the economy, the federal government. By the way, the federal government spends more on R&D than all VC combined.