The east coast has entire Ivy League and yet no Silicon Valley. Also, how do you explain Seattle?

Many of the brightest on the East Coast get sucked into finance.

This. Even ignoring the number of students that go study banking/finance in college, the banking/finance industry also employs many CS and math graduates.

University of Washington is a great university. But it does seem like presence of universities is at most a small factor here.

That's his point, Seattle is a tech center without many major universities.

Seattle because Amazon hires and relocates thousands of engineers there who then quit or are PIPed a year or two later, leaving them looking for new opportunities or building new companies.

Pre-2020 Seattle (I do believe a SF like reckoning is on the horizons for Seattle as well because of political overreach on corporations) in fact might be the exact talent sink and hence danger to Bay Area.

Seattle at one point had Microsoft as the hub, Amazon came on the scenes in 2000s - once they both reached critical mass, there was practically no stopping the growth because engineers had an alternative. Eventually we had FB/Twitter/Snap et al starting offices here and having massive presences which led to present day. If only the weather wasn't what it is, I think we would have reached this ~20 yrs ago.

I don't know if it is going to be Austin / Boulder - but once any of those cities build two equally good employment opportunities, it is going to be a real contender. This is what makes TSLA / Oracle move significant: till now what were outposts are becoming real hubs.

Don't forget non-competes which CA outlaws. Job mobility is key to innovation without worrying about getting sued by your former employer.

If you're a software engineer based out of the NY area, almost every recruiting message you get on LinkedIn will be from a fintech company/bank/hedge fund. NY is probably the second biggest tech hub in the US outside of SV, but most engineers work in one of those aforementioned sectors.

A lot of East coast Ivy League grads simply either go into the public sector, or finance. They essentially feed into either D.C. or New York.

The East Coast had Bell Labs, Digital Equipment Corporation, IBM, etc., all of which were absolute powerhouses at various point.