EDIT: As noted by the sibling post, the reason it is cheap is because Walnut Creek does not have very many tech jobs. Also, the peculiar thing about the Bay Area is that about 15 years or so the tech industry oscillates its epicenter between San Francisco and the South Bay. From Walnut Creek you can reach San Francisco in an hour, but if you have clients/partners/HQ etc in South Bay it is one bad commute.
It's completely dead and devoid of culture.
Even in the Sunset and the Richmond, 1 bedroom rents are still expensive. I poked around Craigslist recently and found plenty in the $2500 range. If you go across the bay, it's a little better. And, if you can deal with BART turning into a pumpkin at midnight, you might enjoy your work commute more.
Edit: this post assumes you take a job in SF. But, big companies are building more and more office campuses on the peninsula, away from reasonable public transit options. If I recall correctly, office rents in the city are actually on the rise, considerably, and it is driving larger employers out of the city under the guise of "putting our employees together to collaborate better."
About 40-45 minutes from SF and San Jose time wise regardless of time of the day.
That’s where the premiums comes from
But even with that commutes are soul sucking. I pay $2.7k for a tiny apartment but not having to deal with a commute longer than 5 minutes walking is amazing for my overall well being.