I used to do mechanical turk jobs for some quick and easy pocket money. There were several types of tasks you could do, and there was a sort of ranking system to dissuade anyone from just inputting junk instead of answering seriously. I usually stuck to surveys and things I would describe as fancy captchas. I recall a few jobs where the task was to record yourself in different environments reading the same script of text. I can’t see that type of job for being anything other than training data for AI/ML
I was never told exactly what it was for. My suspicion was that it seemed more like acquiring training data for an audio processing machine learning library. This was about 10 years ago, so after the likes of siri, but way before something like chat gpt