I'm simply not buying it. If you can't find potential in a candidate pool that's practically in the tens to hundreds of millions, it's more likely your search methods aren't cutting it.
EDIT: But let me specify - the original premise to this was that there are already two comparable candidates in SF and somewhere else in the world.
"Finding potential" and "finding someone to build this thing in a quick and useful way in the immediate future, not the far future" are VERY different things.
I've worked with overseas devs who I'm pretty sure were smarter than me (PhDs, ability to go deep on tons of technologies) yet didn't have the skills needed to quickly turn around a request from a business person and build the right feature.
I think salaries will level out to a certain amount inside the US and other countries - but it's going to be a long time before highly competitive companies wouldn't be shooting themselves in the foot by eliminating themselves from consideration by coastal devs, experience-wise - but cross-country language and communication barriers (especially when timezones are involved) will remain very high.
Companies have already been trying to do that sort of outsourcing for 20 years, and yet US salaries have only gone up in that time frame. Solving "working remotely in the US in a few timezones" is a very different problem than solving the persistent, unsolved-for-decades "hiring programmers in a different country" problem.
It makes sense right now -- those folks didn't get the same mentorship as the ones in tech hubs, because all the senior people who were good moved to the tech hubs until recently.
I think this will normalize over time, but it will normalize to no one getting good mentorship as all the senior folks work remotely.
There aren't "hundreds of millions" of developers on this planet. The talent pool is small because just a small fraction of the workforce worldwide has the training, skills and capabilities to work as software engineers.
Sure - let's cut that number down from hundreds, to millions.
For the discussion, let's assume that the whole world of IT candidates is now your pool of potential employees. India alone seems to produce around a million computer science graduates a year. Europe, probably in the same ballpark. Rest of Asia? Who knows. Same for Central and South America. That's each and every year, new candidates that are added to the pool (minus those removed).
Even the absolute outliers would result in a sizeable number.
You are right, not all of these might have the required knowledge (if looking for experience hire), or some other number of factors.
But it would probably be easier to just start poaching top talent from top companies around the world.
EDIT: But let me specify - the original premise to this was that there are already two comparable candidates in SF and somewhere else in the world.