You're comparing Mountain View, a town of 80,000 people and 12 square miles, to ALL of Austin, with 270 square miles and nearly a million people.

There are incredibly expensive parts of Austin. There are cheaper places in Austin.

The areas where upper-middle class Bay Area tech workers would want to love are not in the cheaper areas.

Mountain View is just an example, and not an extreme one like Atherton or Palo Alto. Even if you go as far as say Pleasanton the market is still in another league compared to Austin.