It’s designed as a temporary display shift so you can to reach an unreachable top button. The intended use is.
- Activate one handed mode
- Press button that is now reachable
- Deactivate one handed mode.
I use it this way all the time. I note that some actions automatically deactivate it.
I have had phones on the past that shrink the whole screen which was more pleasing to the eye but less useful.
The nothing solution is a bit ugly but it works.