Those where the days you could email a webmaster and get a response, when you hung around with like minded people in self-organised communities around a thing that interested them - like reddit without the massive negativity and astroturfing.

The modern internet (or web really) has lost much of that flavour, there are a few places that still maintain it with anonymity - HN is one, specific subreddits, the IRC server I've hung around forever, I've friends on there going back more than 15 years, we where all early 20's computer geeks, now a lot of them are married with kids or have kids on the way - I know a tonne of details about them personally and sometimes don't know their real name.

I do see some echoes of that world in some modern platforms (discord for specific games (in my case Arma) captures some of it).