What job do you think they would be doing instead? And why do you think they aren't doing that job now?
I ask this sincerely. I've worked gig-economy jobs when and only when they were what I judged to be my best option at the time. When I've found other opportunities that had a mix of compensation/flexibility/benefits I preferred, I've switched to do that instead.
My experience strongly suggests to me that the same is true of most gig workers--they're choosing the best of the options available to them.
I don't see how removing their current best option somehow makes a better one appear that wasn't there before.