There were quit a few off them--by number of starts per year per person Caltech was actually generating startups at a higher rate than Stanford. But almost none of those Caltech startups were doing anything that would bring them to the public's attention, or even to the average HN reader's attention.
For example one I remember was a company developing improved ion thrusters for spacecraft. Another was doing something to automate processing samples in medical labs.
Also almost none of them were the "undergraduates drop out to form a company" startup we often hear about, where the founders aren't actually using much that they actually learned at the school, with the school functioning more as a place that brought the founders together.
The Caltech startups were most often formed by professors and grad students, and sometimes undergraduates that were on their research team, and were formed to commercialize their research.
My guess is that this is how it is at a lot of universities.
Personally I think this resource mismatch can help drive creative choice of research problems that don’t require massive resources. To misquote Feynman, there’s plenty of room at the bottom
You get ahead as an academic computer scientist, for instance, by writing papers not by writing software. Now there really are brilliant software developers in academic CS but most researchers wrote something that kinda works and give a conference talk about it -- and that's OK because the work to make something you can give a talk about is probably 20% of the work it would take to make something you can put in front of customers.
Because of that there are certain things academic researchers really can't do.
As I see it my experience in getting a PhD and my experience in startups is essentially the same: "how do you do make doing things nobody has ever done before routine?" Talk to people in either culture and you see the PhD students are thinking about either working in academia or a very short list of big prestigious companies and people at startups are sure the PhDs are too pedantic about everything.
It took me a long time of looking at other people's side projects that are usually "I want to learn programming language X", "I want to rewrite something from Software Tools in Rust" to realize just how foreign that kind of creative thinking is to people -- I've seen it for a long time that a side project is not worth doing unless: (1) I really need the product or (2) I can show people something they've never seen before or better yet both. These sound different, but if something doesn't satisfy (2) you can can usually satisfy (1) off the shelf. It just amazes me how many type (2) things stay novel even after 20 years of waiting.