This is true, and honestly my biggest gripe with the phone. I don't wear small mitts, and I can only comfortably reach 3/4 of the way up the phone. This is exacerbated by the fact that phone application design is in a very top-centric stage right now. I wonder if there's a way I could extend the android nav bar to take up the top 1/4 of the screen...
On Samsung devices there is an accessibility setting that gives a smaller one-hand screen when swiping down from the bottom bar. But that just feels like a waste of space when you could just have a smaller screen.
I ended up buying a Pixel Fold for the Fold aspect. There's an added benefit that it's really short when folded so I can reach the entire screen one handed. It's heavier and thicker than a slate phone, but I actually enjoy the folded experience way better than other phones.