Forums do the same thing, just with pagination instead of collapsing. Newcomers to a thread or FB post aren't going to read through the last 40 pages of comments, but the option to do so is still available.
I started playing on the internet in 91, I used IRC mainly, it was exciting and fun talking with people around the world, not many people were on the internet..... to me it went down hill from there, it started being more of a tool with the various phases of new amusing things :)
other people started at various points and they would go through a similar thing, it's a great toy that slowly becomes a tool but you can still use it as a toy, but often less inclined to do so, mainly because the toy changes shape all the time and the way you originally played with it morphs into something else.
It's gotten to the point that making a perfectly benign comment that couldn't possibly be seen as taking a side or disagreeing with anyone's opinion is insta-downvoted or attacked, assuming it's not parroting whatever the sub's current talking points are.
I'm not even referring to the political/news subreddits, which would be understandably partisan. Other subs that used to be about the topic at hand have started coalescing into us/them teams.
Then again, I'm 36.
For my part, I've spent less time on things that don't matter and more time on things that do matter. So while yes, the web has lost its luster from my teens and twenties, I think my general sense of life fulfillment has broadened considerably.
Or you could go old-school. Fark.com is still around, as is SomethingAwful. Reddit has tons of content. And if you're not at work and looking for a horrifying thrill ride, 4chan. IRC is just kind of depressing after you've been away from it for a while... like, a decade later, these same people are still sitting on these channels every day, all day? Then again, I'm still on this waste-of-time news feed...