Why are post ~'80s bike finishes so "dull"?
This is not a complete answer, but one factor certainly is that nowadays bikes often use powder coating as their finish, rather than liquid paint.

Powder coating has signifcant advantages over paint (more resilient coating, no risk of running, no solvents required), but the surface characteristics are different. In particular, the sparkle effect of metallic paint can not (easily) be achieved with powder coating, and I believe multi-coloured finishes are also more difficult.

So check whether the new bike has a powder coating - that may explain the difference in apperance.