It's too small a city to be widely diversified in terms of tech providers, so whenever a bubble or recession hits, the city takes a dive. There's nothing else within commuting distance with similar tech options (Dallas and Houston are too far, and San Antonio is mostly medical).
I grew up in Austin in the 80s and 90s and watched things first-hand: first there was the mid 80s (1985-86) semiconductor bust (component makers were out-competed by Japan). Fifteen years later there was the Dot Com crash (gutted Dell, as well as dozens of smaller web startups headquartered in the city). Every time the market bust, it was 2+ years before jobs reappeared, making it a dangerous place to call home.
If you want to live there, go on ahead - just make a nestegg your first priority (and take the cost of that into account when you are pricing out the city).