I agree with this sentiment. A 10-year-old bike would be much newer than any of mine as well.

I often hear people talking about how more money buys smaller and smaller improvements. While this is no doubt true, I don't as often hear that each year brings smaller and smaller improvements. The major leaps forward that you mention (and many others) happened decades ago. Hell, I'm old enough at 50 to have had bikes without index shifting or brifters, and they worked just fine as well.