As someone who has always been on fully remote teams, I've found that ease of communication and time zones are a big deal.
If someone is harder to communicate with (English is a second language) or doesn't overlap with the rest of the team's work day and costs the same as a dev in the US, I may end up going with the dev in the US.
People who says pay should be about value provided are ignoring several things, including: 1) I have no idea how valuable someone is before I hire them, and 2) it's much easier to trust employees who are in the same legal jurisdiction as me (which has a value).
For example, I have two devs in South Asia who cost half of a US dev each, but they're also not very independent and they have very limited skills. They make a lot of money for their country and the price for the value is exactly right for me.