Called this last year. This will become more prevalent in the industry as time goes on. Tell your boss you’re moving to San Francisco and if your employer bases your salary on your zip code then your pay should be going UP
However, I suspect that one reason the housing market has gotten so crazy (California perspective here) is that many Silicon Valley tech folks bought houses in Sacramento/Tahoe/$CHEAP_PLACE while also keeping their houses in SV but renting them out. As long as the rent payment covers most of the mortgage, they build equity and eventually own the house, while also having a nice big house to work remote from. And perhaps they quietly keep using the SV house as their official residence for HR/tax purposes.
But I agree we may be headed towards a future where pay is no longer a function of location. If you can't tell where an employee is physically it's a lot more difficult to have location based payments. A remote employee can be anywhere. When I worked remotely (way before the pandemic) I spent some time working from Hawaii and my employer did not even know.
Facebook will also scale salary by location; I have never and almost certainly will never work there but they said they will check VPN logs, and in the past have used IP and geo data from their app to determine locations of employees and users who were potential security risks. Regarding VPN and remote work:
https://fortune.com/2020/05/21/facebook-permanent-work-from-...
<quote> Facebook said it would enforce the new work-at-home policy mostly by the honor code, but that it plans random checks of employee VPN addresses—the tool used to securely access the company’s network remotely—to confirm their locations. Any employee that is caught lying will face “severe ramifications” as it could affect some of the company’s tax filings, Zuckerberg said, adding, “You may be breaking the law.” </quote>
I don't want to second guess them but random spot checks seem like more work than an automated job that looks at all vpn connections and matches to primary employee location.