> multiplier is roughly the same even if the dev in London is working at the exact same company as the one in SV
Sure. Because they’re doing different work, in proximity to different people and different resources, within different economic contexts. A developer in Silicon Valley is fundamentally more productive than one in London, in part solely by virtue of being in Silicon Valley. (Not true at the individual level, of course. But statistically, of course.)
Yes, the setting is different but its different because people can't just go around and work wherever they find employment because there's artificial barrier called nationality and visa.
Sure. Because they’re doing different work, in proximity to different people and different resources, within different economic contexts. A developer in Silicon Valley is fundamentally more productive than one in London, in part solely by virtue of being in Silicon Valley. (Not true at the individual level, of course. But statistically, of course.)