There are many niche subreddits with deep knowledge about their respective subjects. This knowledge comes out in product recommendations, discussions about interesting nuances, and as a place to share original creations (which I don’t think should be undervalued, even if one is an advocate of personal websites—I think content aggregation and easy posting does have value). Subreddits that personally come to mind are /r/fountainpens (a wealth of knowledge on maintaining and restoring pens), /r/mechanicalkeyboards (fascinating when it comes to custom boards), /r/watches, and of course /r/buildapc (an unparalleled resource of computer building lore for part compatibility, build failure debugging, etc). I’m certain there are plenty of other subreddits that provide similarly excellent value for their communities. Why should anyone have to log in to Reddit just to read someone’s post on /r/buildapc about how they should fix their unique issue?

My experience with Twitter is more limited, but I know people use it as sort of a microblogging platform sometimes and it benefits from the same ease of posting+content aggregation setup I mentioned earlier.

This is all my take, of course! I just hope we can avoid balkanizing the internet, despite all of the incentives these social media companies have to do so.