There are middle-men companies like Scale that recruit thousands of remote contractors, probably through other companies they hire. There are of course other less known such companies that also sit between the model companies and the contracted labelers and RLHF’ers. There’s probably several tiers of these middle companies that agglomerate larger pools of workers. But how intermixed the work is and its scale I couldn’t tell you, nor if it’s shifting to something else.

I mean on LinkenIn you can find many AI trainer companies and see they hire for every subject, language, and programming language across several expertise levels. They provide the laborers for the model companies.