I'm happy this is work that can help uplift people in third world countries and I don't want the work moved elsewhere.
However, Open AI can absolutely afford to pay more than $2 an hour for this sort of job, irregardless of the local economy and who does it - and they absolutely should.
Thinking you can have both higher wages and jobs in unstable countries is either advocating for state-mandated outsourcing or is wishful thinking.
Your statement is problematic, because (a) clearly at some point "less bad" stops being what anyone defines as exploitation, and (b) if you're not living in the tradeoff space, you're not qualified to judge where that crossover is.
There certainly is exploitation to be found*, but paying a multiple of all other opportunities, even if that multiple is below what is available in a different context, is not exploitation.
It's putting a thumb on the scale, accelerating the tilt towards equity.
* There are articles about labeling or screening done by workers in USA that are as PTSD-inducing as the linked stories, where people were paid US wage and had to quit. Don't confuse the job with the pay, these are two different issues.
// Disclosure: I grew up in central Africa. In my teens I worked in the local tech economy, not the expat economy.