This is 2015. Some of us would have thought that by now, location would be a factor mitigated by technology.
Not everywhere is 'cutting edge', in terms of resources and managerial ideas, so it helps to think outside the SF bubble. I used to have to spend 2.5 hrs in traffic despite working for a 'tech company' just b/c the boss (late thirties) wanted it that way. And there's not much arguing with the person that cuts the check.
Do you want to be surrounded by people on the cutting edge of tech? They all congregate in one or a few places, and you have to move where they are to reap the benefits of community.
People will always seek to associate in meatspace, regardless of society's tech level.
When I moved here, people came here because this was the place where all the interesting technology happened. It was hard to keep up. But now, the number one reason to move here isn't the technology. It's access to capital.
Since Bubble 1.0, the Internet has become an excellent distributor of technology. But VCs still aren't interested in getting on planes.
Not to mention living here is nice for many other reasons.
It is a swell place to live, though. But even that advantage has declined a fair bit. 20 years ago, a lot of places in the midwest were cultural deserts. Books, movies, magazine, ideas: all severely restricted. The Internet has changed that. And San Francisco is rapidly losing the diversity of culture that was a big draw for me.