GUI scale slider is broken

The bug:
The GUI scale slider only has 2 options: 0, and -1. 0 is too large for my taste, and -1 is okay but I would still prefer the option to go smaller. In previous versions there were more GUI scale options. This issue exists on Windows 10, PS4, mobile, and Nintendo Switch. I am unable to test this on Xbox One.

How to reproduce:

1. In settings, select the video tab.
2. Scroll down to the GUI scale slider and take note of how many notches there are, the numbers they are represented by, and the GUI sizes they result in.