[actually_a_dog]

Yes, and they exercise their leverage by applying to those SF or NYC companies from wherever they are. If they can exercise that leverage from anywhere, then how is that not having leverage?

These companies are used to this sort of thing. Relocation costs are nothing compared to the cost of hiring. There is effectively no friction on the company's part. Yes, the employee needs to be willing to go through the process of moving, but, provided they're willing to pay those costs, their leverage in the situation is unchanged.

[machinebun]

Those frictional costs (of moving) are the whole problem. SF salaries are where they are at because of those frictional costs (people choosing not to move to SF, whether by personal choice or by way of visa restrictions etc).

Yes, there is a subset of people that have disproportionate leverage no matter where they are at (by virtue of being really really good devs). But that represents only a minority of SF devs.

[TulliusCicero]

That's just the thing. Companies know that, at any given point in time, many people will be unwilling to pay those costs.

A family of four enjoying a large house in some suburb for a reasonable price may find the idea of living in a 2br apartment in SF, or paying a truly exorbitant price for a single family home in the bay area, unappealing.