[ACS_Solver]

I don't really find reddit comparable to forums, mainly because reddit is also built around recent comments. It has very rudimentary search functionality, and the way submissions and comments are scored discourages long conversations. Unless you're on a really small subreddit, stuff falls off the first page quickly, and your comment will be far less visible if posted half a day later. This is completely different than forums, which optimize for conversations that last for several days to a couple of weeks, sometimes much longer.

[Lucadg]

Exactly. Forums optimize for quality content and this makes it hard to monetize them because when you found the good stuff you are not going to click on ads.

Also, mobile which is not ideal for long conversations helped their demise.

Still, I hope they come back big time. I miss them.

[krapp]

The forums I hung out on simply sorted by the last comment, or by votes. They certainly didn't "optimize for quality content" in any particular way, other than banning trolls (sometimes.)

Also plenty of good forums had ads. I don't think it's a common thing to want to refuse to click on ads because of high quality content, I would guess the opposite tends to be true.

[Lucadg]

I probably have a too much romantic memory of them :)

Anyway, it was easy to come back to a specific topic, so it was easier to find good ones. You could bookmark them, see the number of views/replies or even find them in search engines.

Good content surfaced and survived better, so optimization is probably the wrong word.