Lived and worked in Austin tech 7 years. This article is all about startup funding, plus it quotes one unicorn whose home base / frame of reference was Houston, not another tech hub.
Austin was always a great place to build a tech career if you, for example, had a family. The talent pool is great but, in my experience, has a lower risk tolerance (read: prefers bigger and more established companies) than SF. So if you're evaluating by startup formation or funding, sure, the Bay was and remains in the lead. And as that stuff dries up, it's going to dry up faster in Austin, because the culture in Austin always had a slant toward optimization over disruption.
For the big SF/Seattle-based companies, Austin seems like a cheap second city. For a Houston-based startup, Austin seems like an expensive second location. And for a new startup trying to take risks and go big, the Bay is just set up better for it.
I don't see this as losing a luster. I see it as... very little change at all.
Cloudflare, Crowdstrike, IBM, and Oracle's investment in ATX will help it massively
The network is much stronger in Austin over NYC, and there is a better established pipeline between the ATX scene and the Bay plus Seattle. Also, I've found Texans operate on a similar wavelength as other West Coast folks. And you can't discount the absolute behemoth of a pipeline UT Austin and IBM Austin is - something that no university in NY-NJ can compete with (come at me salty Rutgers and Columbia bros /s)
Austin is big enough that you can have a self sustaining ecosystem, but small enough that you can still experiment. On top of that, there are enough early career PMs, Sales, SWEs in the area to get startups off the ground.
I've also found the NYC scene to be immature and piggybacking off European/Israeli founders trying to build a US beachhead due to American VCs.
I simply can't think of a recent major IPO from an organically grown NYC tech startup. Spotify was large, but largely built out of Sweden.