No worries, not suggesting you think it's slavery. I think that would be a pretty extreme position to take.
I do agree people aren't always rational, and there are certainly other costs in terms of wear and tear etc.
But I think people are (1) relatively more rational when it comes to money, (2) get more rational with experience (i.e. as they observe having to take their cars in more after driving a while).
Uber has > 160k active drivers, I think it's very paternalistic to suggest they aren't rational enough to realize how screwed they're getting and think gov or some other third party needs to step in. I think it should also give us pause that many of the loudest voices saying these things (especially locally) are associated with the taxi industry.
These researchers say it's $8.55. Some people argue it should be more (like $13), but -- like I said in another comment -- a job is a bundle of things including pay but also: flexibility, liking who you work with, feeling like you accomplished something, etc. Uber provides very high flexibility (literally can almost work on demand), which economists have estimated gives drivers twice the surplus over similar paying, less flexible options.