Do We Need to Subsidize Car Use?

There's evidence that the rise of uberan lift had some effect, but it was relatively modest. If one reason to have really great public transit is to increase mobility generally, and i don't know of a single economist, or other social scientist, any scientist, who doesn't think that increasing access to mobility at least, is a really good thing. Rather than building these monstrously expensive public transit systems, would it just make more sense to buy cars for low income people?