No idea on the specifics, but the theory goes like this : clients have been burned many times over cheap solutions. Cheaper is usually more expensive on the long run. For this to break the circle you need reputation of reliability.

I didn't nor do I use Upwork. I'm just saying what the reality is.

If you're in the US, restricting yourself to jobs where they are limiting to the US results lessens that problem (doesn't eliminate it - I suspect there's a ton of fronting accounts)

I've tried it on the buyer side and anything less than $50/hour can't speak proper English. It's definitively cheaper but not significantly; and if you add the struggle of going through all the profiles, then the price will match reality.

Just wait till chatGPT hides this telling input signal. I mourn for humanity.