I believe that more "gig workers" are hustling trying to turn an easy to get job (food delivery, ride share driver) into something resembling a living wage because they can't find other, better-paying, more stable work, than are students, retirees, and empty nesters trying to make a few bucks in their spare time. I have no proof, but that is my impression based on my experience.
That's the crux of the difference of opinions when people talk about gig work.
(Side note: if a job is easy to get, it's not going to pay super well. Supply and demand, and all that.)
My understanding based on interviews with actual gig workers is substantial numbers of them are just supplementing their income with gig work. The canonical examples are students who need beer money and retirees who want to supplement retirement income and get out of the house for a bit.
I have no doubt there are also people who are trying to make a full time living doing gig work. Driving a taxi was never a great job in terms of income, I don't see why we'd would expect driving for Uber or Lyft would be any different.
We also have to realize not all gig jobs are the same. At one end of the spectrum is food delivery: that's a low skill, relatively low value occupation. No kidding it doesn't pay well. I got paid a pittance when I washed dishes because anyone could do it if you could put up with the sweat, exhaustion, and smell.
On the other end are people like freelancers and the factory workers in TFA. Those are high skill, high value jobs which people really do hold as full time positions. But there are many people who apparently don't want to work full time 9-5. That's not me, I like having a steady job, but that's the point: my preferences and the preferences of those people are vastly different. I don't see any reason why I should have any say in what work arrangements other people are willing to agree too.