Do those pay competitively compared to a good salaried position at a big US company? On a per hourly basis of course. Most of what I see in hourly positions is far below what I'm used to.
It varies. I've gotten calls about gigs that are laughably low, and I've gotten calls about gigs that are above market value for corporate work. Corporate work is never as high as FAANG or even most SaaS companies, though.
I hear about above market rates when it is about niche skills. Think about what you know that is an uncommon skill and look for contracts using those skills. If you have a collection of unusual skills, find contracts that use them all. My best hourly gigs have been migrating apps from one obscure tech stack to another.