Often because (as in this case as well) they are not regular LCD or calculator-like segmented displays, but rather Vacuum Florissant Displays. VERY satisfying hue they emit.
Old gas-plasma displays are awesome there’s something so retrofuturistic about them, they’re a cross-breed between CRTs and LCDs.
Some laptops specially those for mil applications came equipped with them they also were (and there are some still running) common on industrial machines due to their ruggedness.
In recent Etak article comments webstrand linked to this gem: "INFORMATION DISPLAY - The Official Journal of the Society for Information Display" JULY 1985 VOL.1 No.7
In about 20 years from now, you you could write this exact same article but instead of Oldsmobile Trofeo and Trinitron CRTs it will be LCDs and any car sold today.
Something super satisfying about the colors and contrast.