From friends I've talked with, the benefits of the valley are real, but diminishing. At the same time downsides are increasing: cost of living, homelessness, real estate prices (though I read these are coming down a bit). I've been told the benefit has been the ease of networking, and likely will always be so. As startup hubs grow around the country this networking benefit will start to be there. It is already there…
People have been saying this for a very long time. I did a startup in Pittsburgh back in ~2009, and this was exactly what everyone was saying. My cofounder is still doing startups in the same space(ish), but in the Bay Area now. That doesn't mean it won't ever come to pass, but I am still skeptical. (And I live in Austin now... but the startup I work for is still fundamentally based in the Bay.)
And yet, and yet, and yet the same centers of industry persist. Movies in LA, Oil in Houston, Finance in NYC and tech in San Fran.
I am sure the arguments for the persistence are well rehearsed and can be looked up but I just want to underscore one feature: winner take all.
Whichever argument you find compelling as to why these industries congregate, (networking is easier, money is easier to get, you have everything you need in one place, ambitious people go there and so on) it has to be such that the #1 place has an enormous advantage over the #2 place. If your argument does not have that structure, it doesn't really explain why everyone congregates.
And if your argument does have that property (some winner-take-all mechanism), then after covid and zoom force a redistribution, so long as that small advantage maintains, the dominant city will re-assert itself.