Reddit and Facebook are not a single community, they are many communities some of which have a very high bar for quality, and some of which are a free for all that tends toward low quality memes and trolling.
In the old design you could go to /r/subredditname/comments and see an ordered list of comments regardless of which post they were associated with. It really livened things up and let you track the conversations going on given that there wern't that many new posts in a given day. That's gone with the new design unfortunately.
Example: https://old.reddit.com/r/sweden/comments/
I have disabled the new design entirely in my user preferences, so I get the old design even if I don't put "old" in the URL.