Some issues I see in real life that make this up:

1) Everyone is very dumb about maintaining relationships. No comprehension that without a workplace or other physical commons where we meet, there is absolutely no "water cooler". A forum is a water cooler - you meet up, exchange pleasantries, and stay reminded of what people stand for and think about. After a couple of years I hardly remember someone that I haven't talked with regularly. I vaguely remember many of the high profile personalities on CCF but it was a long assed time ago, too.

2) Most people are zombies today. They may or may not be on Netflix or gaming but they have no energy to converse. They may say they have no time but really they have no energy to spend even discussing something.

3) Cowardice. Being unwilling to meet any level of disapproval for one's opinions. However, it is extremely stressful to be attacked even anonymously on a forum because it's still "you" even if you are just a screen name. I've tried to tamp down, discourage and combat personal attacks on boards I've run because people shut up and shut down and don't want to provoke the mob when attacks are frequent. But that requires a huge amount of psychic energy to do so and I got blamed constantly anyway. Not strict enough for one faggot, not free speech enough for another faggot. "Faggot" meaning a complaining forumer.

4) Intolerance of forum-level opinions, mindsets or the owner's own opinions. I know for a fact that I drove a ton of users off of CCF by indulging the right wing politics. To which I said and say the US is a gigantic declining dumpster fire, of course you need radical change. But that message is too over the top and harsh for many normies, many of which happen to be IT types on a message forum.