It’s OLED screen, which burns out. If you forget to turn it off. it will get damaged in long-term perspective.
I suggest to use simple snake of letters rolling through screen in random patterns - snake can hold branding, as well as will not be static load on pixels.
On my XR, the displays goes to sleep mode after a short time without usage (laying on the floor or desk). It doesnt completely turn off the displays but it turns the image black at least. Good point though, a random screen saver could be an option.