Unpopular opinion: Silicon Valley is in the beginning stages of a period of decline. There's lots of great entrepreneurial activity elsewhere, and for building these sorts of "hard startups", the truth is that SF and SV are not the best places to do it. People and rent simply cost too much, and the venture scene lacks depth in these areas.
I disagree, having worked both outside and in the Bay Area.
The network effects are unparalleled. We're paid far better (my salary nearly doubled when I moved to the Bay, my rent didn't). It's far easier to find quality talent and freelancers for startups than elsewhere.
But most importantly, the money and culture is here. Raising money outside of the VC scene here is orders of magnitude more difficult and you get far less for the time you spend.
And I could go on about how places I've been (South Florida, Chicago, Research Triad, etc) all claim to want to be the "next Silicon Valley" but they won't. Partly because SV didn't become the "next" anything, it garnered a unique culture that funded massive amounts of innovation, and anyone chasing a trend is too late. But mostly because the money and tech people in those cities are too cowardly to do anything truly innovative, by and large. There are outliers, of course. But frankly there's not a lot interesting going on anywhere outside the Bay and it pays way, way worse.
Not for the sort of "hard tech" that Samalt is talking about here. Those network effects aren't as prevalent for those working with nuclear fusion, or space tech, or advanced materials, or battery technology.
Yes, you can find lots of brogrammers cranking away at the next advanced app using React, etc. in the Silicon Valley / SF / Bay area and get paid better there for doing that sort of thing. For that, Silicon Valley has the tech in spades.
But if you want to start an advanced lightning company, for example, the Research Triangle (not Triad) that you refer to above is the place to do it. It's the home of CREE and many other LED innovators. Not Silicon Valley.