I have an 86 Spectrum and an 03 Tallerico. Both amazing.
There's no comparison though.
Ergo bars, ergo shifters, shift ramps, titanium and carbon fiber bits. There is a little more than 4 pounds difference. One rides like I'm cruising country roads and the other like I've got the full weight of the pro peloton chasing me.
By every objective standard, the newer bike is better. I don't know how to measure fun, for me that changes depending on the ride.
I think there is a point of diminished returns though, I can't imagine a brand new Tallerico with brand new Chorus would be much different, just a little lighter with a larger steerer tube.