Location-based pay has been the norm at Apple, Google and Facebook already.
Then, consider that much of compensation at higher levels is RSUs you've already been allocated for the next four years anyways.
Yeah. Anecdotally, the adjustment in pay within the USA at Big Cos is much lower than the differences in housing costs between SFBA and everywhere else.
(Between countries is another matter though; several years ago I've heard of folks in Europe making 2x/3x less than their American peers. Not sure what the situation is today.)
From what I've read elsewhere on the internet stopping the flow of CA programmers would actually be a god-sent to people who were raised in Nowhere, Montana, the gentrification taking place in the last few years has had very annoying societal side-effects for said local people. As far as I could understood Colorado is already a lost case, though.
If you aren't working for a major publicly-traded big tech firm, chances are this is not going to be happening to you in the first place. Big tech's motivation for doing this is clearly cost-cutting and avoiding liabilities they cannot yield total control over. If Google can't get you fat & giggly on paternalistic "benefits," hosted on their corporate campus, they're afraid you won't become the subservient non-skeptical workhorse they believe they need. So, they've got to start finding ways to offset the costs they believe will be coming from having employees who aren't being dominated under the total surveillance and control of Google's ever-present watching eyes.
And furthermore, who's checking all of this—do you have to prove where you work, or just have a mailing address and a place to pay taxes?
I know one place that sent an inspector to verify the home office had the minimum required office equipment: a door and a shredder.
I'm not sure exactly how sales tax rules work, but in the US I believe that if a business has a presence in a given state they are required to collect sales tax in that state. This could matter for smaller companies but probably Google already has a presence in every US state.
Regardless, purposefully lying to your employer about your location seems like something most employers would get really upset about simply on principle once they found out.
That's it, the end of geographic arbitrage. No more working from the mountains on a Silicon Valley salary. Hope everyone enjoyed it while it lasted.