Frequently it's their only option, the only job the have access to, so in a way, you're right.
They're not dumb, just constrained.
One can stay here debating all along why people get to those situations in the first place, and that normal jobs shouldn't require extra work, or that immigrants should be able to find easy "normal" jobs etc, but the point stands for me that a world where I can pick from three options (full-time, part-time, gig) is better than a world where I can only pick from two.
That being said, I'm supportive of more regulation around gig-work to protect gig-workers, but that regulation needs to be specific to gig work and not just force it to disappear outright. A gig-worker shouldn't be able to be kicked out without explanation, there should be recourse for customer ratings, they should be covered by some kind of global insurance, etc, but these things will need to be tweaked to this new reality instead of us pretending like there aren't many many people around the world that prefer this work arrangement.
You've been told multiple time people value flexibility and yet you keep fixating on an old work model that you want to apply to everyone. More options are better. Full time jobs didn't go away. This whole industry didn't exist other than getting paid per shift as a pizza delivery driver.
How many gig workers do you personally know? I know more than 20 and all of them prefer gig work to signing up for a full time delivery position at a restaurant.
Gig work is available to immigrants super fast as well. Go to any major city in Europe and see migrants and refugees making a living delivering food. Do you think they are dumb and choose the worst job they can get?
Talk to some people before you pontificate over what they should want for themselves. They can literally stop the app at any point so your problem isn't that gig work exists, but that other people value things you don't.