I had to sleep in my car from time to time when I was in college.
I'd park in a well-lit spot in an active parking lot (back in the before times, many major retailers were open 24/7) in a safer part of town. The backseats of my car were pull-downs that opened directly into the trunk. So, I'd sneakily climb through and into the trunk, then curl up back there to sleep.
It was a dark space and since nobody could see me back there, there was less chance of someone targeting me for robbery (sleeping person = easy target) or calling the cops on me (sleeping person = drugs or medical emergency). But those were still factors that added lots of stress to an already shitty situation.
I know times are harder for more people these days, but I figured I'd share since a lot of people don't actively recognize that things were also difficult for many people back in the day as well. While there's obviously a problem that needs to be solved here, and it sucks that we're at a point where this is considered a solution, I would just say, don't let perfection get in the way of progress.
Of course we should strive for a situation where everybody has a home, familial / social supports, good stable income, etc. But, also, even a little added comfort from having a safe(r) place to park & sleep as well as access to things like showers and bathrooms is a tiny little step in the right direction.