Just FYI, if anyone is thinking of ordering a Defender with the head-up display, and if like me your day-driving glasses are polarized prescription shades, the polarization sure cuts out most of the HUD brightness. I guess I should have known that's how light works. You can't change the laws of physics but it's nothing that a quick head-tilt won't solve lol.

 

I believe it also is the way your glasses are cut. One pair of mine see it and one do not and both are polarized.

 

Mine is a MY2021 and I do have head-up display.
Depending on which sun glasses I wear, I can go from a slight dim ( cheap sun glasses ) to polarized, where I lose quite a bit, and to circular polarized sun glasses, where I have to keep the head tilted at about 45 deg which would make the display visible again ( not recommended )
Do I like the HUD ?
LOVE IT ... some times when I am in a new area, and use the maps, I even forgo the glasses, for convenience of HUD.