They have the power to vote, arguably much more influential then money.

> They are too poor and too desperate to be unemployed for long

If they are too poor, they also qualify for food stamp and a bunch of other benefit that YOU are paying for ! Its a transfer of wealth from your work / pocket to rich Uber shareholders like Saudi Arabia.

> and many will be replaced with robots.

Unlikely, especially for last mile, and in cities ( where most people live )

> The gig economy is an underclass. They are serfs.

Most of us are "serfs" to somebody, unless you are retired or are living off your investments.

> Unless they rise up violently nothing will change.

Not really, they just need to vote, DJT is an example, Bernie maybe next.