And what makes it possible for lots of startups to exist? What makes it possible for upstarts to rapidly rise and replace an incumbent?

Todays Big Tech replaced the earlier generation. But the markets have been so thoroughly captured that it seems impossible for any startup to replace Meta or Apple or Google. Netflix is struggling not against another startup but industry incumbents replicating its technology.

Until the markets get competitive again, there won’t be much innovation domestically. TikTok should have shocked the entire US tech industry but rather than try to come up with better products the Tech industry tried to dismember the company and gobble up its US assets ( a process that stopped only because of a change in administration).