The company where colleagues decide your salary

I'm not even sure anymore that local demand / supply should affect it either.

I'm still not sure what the right approach is but I can think of a few arguments against this practice.

Re: COL, is it on the company to adjust your pay based on your environment? Should they then not also pay a father of 4 kids more money than a single one (in the same location)?

More generally, consider what different pay based on location does to morale: Say for a single employee in the US / SV the company could afford 2 to 3 employees in India. By extension that makes an US employee more valuable as the company wouldn't spend that much money if they weren't sure that employee delivers more than 2-3 Indian employees. But do they? Wouldn't the US employee then by definition have to be in a higher grade (title) as well?

Also take into account that it's traditionally harder to get promoted if you are not close to / in HQ, so Indian employees would already be at a disadvantage.

I don't know what folks in India think. Maybe worrying about inequality is something people have given up on, but I'd personally avoid a company that "transparently" told me I was worth less for doing the same job just because of were I live [2]. We don't like when that happens to women or underrepresented groups. Why should we be okay with it in the context of globalization?

[1] FWIW, they say their formula does take COL into account, so not sure what's going on.

[2] In fact, and sadly so, I'd probably go for a company that is generally known to pay well but not transparently, instead, even if they end up paying me less than US employees as well. At least nobody's claiming fairness there.

I'd want to make Cupertino level software engineer's salary while living in Eastern Europe and paying 300-1000 USD/month for all living expenses

It's """your""" choice that you want to stay in SF, I guess?