I started riding and racing on the road in the mid 70's. It was definitely simpler. Milage for a given ride was always approximate although then and now training was/is more about time on bike than miles. Everything was by feel, you really had to develop a good feel for what now would be a well defined Power/Duration curve. The only history is what I kept in a journal.

I think in general it steered you (at least me) towards even small group rides over solo as a way to sort of "legitimize" your effort with your peers. Now I can throw down a solid solo effort, that in the past would have been totally between me and the road, and get instant positive reinforcement. So there is a loss of one motivation for group over solo rides.

That said I enjoy all of the new tech. Went from PE to HR to Power. Strava early on & was a Beta Zwift rider.

One thing you youngsters are going to miss out on. You will never be able to play the "older I get the better I was" game. Because everything is a matter of public record