Well, speaking as a typical Joe who cycled as a kid until the mid-1980s then took it up again in the late 90s as an adult, definitely indexed gears. Before that, I used about 4 gears on my racer by mashing the chain against the stops. Just behind that, SPDs.
But overall, probably that mass-market general purpose bikes are so much lighter, not just fragile and expensive racing machinery. A pretty ordinary hybrid can be 11-12kg instead of a 16-18kg utility bike of 20 years ago.
I think one of the reasons the general public aren't into cycling so much is they aren't really aware of home much better cycles and equipment are now compared to their youth.