It’s really only a small percentage of companies doing that, although the tech scene in Austin has definitely been growing. Even when I was visiting Austin in the 90’s, it was starting to get that Silicon Valley feel to it.
Education-wise, both colleges are probably going to offer a similar education. Job-wise, being in Austin near so many jobs would make it a little easier, logistically, to find your first job after graduation. If you clearly feel more comfortable at one of the schools, go there.