A lot of the ground truth for AIs (and it's not just training data - it's also ongoing validation of quality) is coming from companies like Appen, Sama, DefinedCrowd, Q Analysts and many others. There's a lot of variation, but the trend is moving towards low-wage/gig work/outsourcing.

I think Paul means someone will be writing content, but whatever the form it's going to be a whole class of low-wage workers enabling tech from here on.