You're right that these companies could lose steam and this shift could never come. On the other hand, the macroeconomic stats could change incredibly quickly s

You're right that these companies could lose steam and this shift could never come. On the other hand, the macroeconomic stats could change incredibly quickly since these companies are growing exponentially. E.g. if a company is doubling every year, then by the end of 2017 they'll have 8x more freelance workers than they did at the end of 2014, 16x more in 2018, and so on. Based on how big of a change this could be it seems worth at least starting the discussion now rather than after the shift has already happened and there are millions of people without the protections they need. Also, with the Uber example in particular, they have their sights set on disrupting car ownership, not just the taxi industry. So there's a chance it will be a huge net shift.