The only fair way to adjust is based on value to the company, and what the potential employee is willing to accept. It isn't reasonable to use pay to remove the financial advantages of a candidate's choice of location, and then claim "you can now hire the best people on the planet in any particular function" as the original link does. If someone is among the best people on the planet, they'll likely be paid considerably more than the San Francisco average without regard to what their costs are.
One of the touted benefits of working remotely, for those who can, is exactly the ability to trade off the advantages and disadvantages of living in places with varying characteristics, and it's unsettling to have a company which claims to support and encourage remote work also be upfront about actively working against remote workers' ability to make these choices.