There's truth to that, a lot of it depends on that developer's language skills and business network.

If you're a developer in the Ukraine with great English and reasonable business skills, you should be able to land a pretty good dev job with a global company.

Another, just as good dev in the Ukraine that only knows Russian/Ukrainian, will have much harder time and will likely be limited to working with just local companies, significantly limited with options.

It's also about leverage and options. I'm familiar with the software dev world and the circus world and am a professional in both - and I've been on circus contracts where I do practically the same exact job as someone from the Philippines (on the same exact show) and yet get paid 2-3x as much. It's price discrimination based solely on nationality and your alternative options, and I've seen it in person. In fact - I am a dual citizen, native to both cultures (moved at a very young age); if I applied for a contract using my U.S. passport and my foreign passport, I would get two very different offers in terms of compensation, for doing the exact same job.

The people spouting "it's all about how much value you produce" are so naïve and ignorant of their privileges / market realities that it hurts.

With devs the compensations will match only when the good foreign developers have just as many alternatives as the good U.S. developers (or at least close to parity - exact parity will never happen due to jobs that simply can't be offshored - contracts with government agencies, for example)

This is totally on point, it's true when you get people in as contractors or outsource the work.

But, if you onboard people into your startup I don't think most people would consider it a wise strategy to underpay certain team members that are part of a distributed team based on where they live..