Much like airbnb, if it was true to its original mission, it would work well, aka people looking to earn some side cash. But if you are working a low-paid driver "0-hour" contract job without health insurance and a self-funded minimum cover insurance and no PTO, sick days or benefits, that kind of sucks.
I’ve read convincing arguments that while drivers may believe they are better off, the cost/income numbers are such that drivers essentially break even. If true, Uber is merely taking advantage of their drivers lack of sophistication re: vehicle wear/depreciation, and the drivers are not actually better off financially. Even if we find no ethical complaint, a shift in the cost/income value perception by drivers seems like a notable risk.