Not really. I've lived in both and the salaries are maybe 20-25% lower in Austin, but everything else is much cheaper for more value. Especially when you're paying for grown up stuff like 3-4 bedroom homes in safe neighborhoods, day care/nannies, etc. That stuff is off the charts expensive in the Valley. And your tax bracket is higher along with your salary.
I can't imagine being an entrepreneur in the Valley with kids without at LEAST a few million in cash. In Austin you only need 1. :)