Nearly all commercial plastics available now were available back in 1997. Even exotic things like PEEK.
The yellowing is due to flame retardant additive to ABS granules. Modern flame resistant ABS stock is prone to same issues.
Re:Why things might have taken so long
by simonbarker87 on Thursday January 04, 2018 @10:14AM
(#16070867)
We use a heat-resistant ABS, 20 years ago it would have yellowed, now it doesn't.
So we needed materials science improvements to make the product viable. I don't think I was advocating for low hanging fruit but instead progress in various fields allow other things to be invented, some of them I guess become low hanging fruit.