Earlier quoted context omitted.
SV companies are not price sensitive. They'll pay alot, even just for the benefit of having them in the office. Software companies either win big or lose big. If they win big, they can easily cover whatever cost of salary in SV and there's still a plethora of talent out here in the bay area, for a well funded company.
I think you're describing a certain type of software company - one that doesn't have to answer to shareholders (Google, Facebook, Snap, etc) and thus behave according to what their leader and employees want. Most of the tech industry (including for example Apple and Amazon) isn't like this.
All of the big software houses compete for the same engineers, and they're all paying their incremental new engineers +/- 10% the same total comp across the experience spectrum.
I would agree with pascalxus, the big tech companies aren't price sensitive.
That doesn't mean the average engineer can easily finagle a drastically out-of-band salary, but the bands are already exceptionally high and grow faster than inflation in the aggregate.