Similarly, the Bay has been the center of tech since 60s. But the Bay is much more fragile than New York; it is largely dominated by the tech industry. So a better comparison might be Detroit. When the car industry left, the entirety of Detroit was hollowed out.
Additionally, you need to be in New York if you want to "play in the big leagues" in the world of finance, fashion, art, etc. But tech has already embraced the remote model. 5-10 years ago, I would have felt like I needed to be in SF to further my career in tech. Now, I live in Austin and don't feel like I'm missing out. If anything, it feels like there is way more startup potential here – people actually building cool things, as opposed to resting and vesting at the big companies that dominate Silicon Valley.