Blue LEDs were deemed a huge breakthrough at the time; they enabled full-colour LED displays (think large panels viewed from a distance) by adding the long-missing B in the RGB.

Indeed, and they are also the basis of single element white LEDs, which are a blue led covered by a white phosphor. The inventor of the bright blue led worked for a chemical company that made phosphors, and invented the white one as well.

They also enabled bueray DVDs.

Enough of a breakthrough to be worthy of a Nobel prize, even:

https://medium.com/predict/why-blue-led-earned-nobel-prize-i...