I think the gap between 1978 and today is so big that denying just how great most of the changes have been is just being curmudgeonly. BUT a lot of the biggest changes happened before 1995. Think about it - by 1995, we had Hyperglide, SIS, brifters, and dual pivot brakes. Those were big leaps. Everything since then is more incremental. The difference in performance - not just speed, but all aspects of performance - between my 1982 Lotus and my 1996 Ritchey is bigger than the gap between the Ritchey and the 2020 Canyon.
Oh, and I can work on all my bikes myself with simple tools. I actually had to buy MORE specialized tools for the older bikes.
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"Don't take life so serious-it ain't nohow permanent."
"Everybody's gotta be somewhere." - Eccles