I agree with your point: Some are choosing to drive for Uber/Lift because they don't have any better alternative. Where I disagree is the solution.

If you raise the price of cigarettes, people buy fewer cigarettes. If you raise the price of gasoline, people buy less gasoline. If you raise the price of labor, people (both companies and individuals) buy less labor. If the price of Uber/Lyft increases, the number of rides will decrease. That means that drivers will be forced to work fewer hours or to find another job. But if (as you say) this is the only alternative they have to homelessness, then they'll become homeless.