I enjoy forums, and have done since Usenet days, but many younger people move to Facebook which can kill some forums dead.
For example ... about 8 years ago I moved countries and joined an expat forum. It was great - I would arrange events in my city and loads of people turned up, plus there were always new members to keep the forum feeling fresh (at the expense of repetitive topics). Over the years, the newbies dried up, and the forum was full of "I've just moved here and have no friends" only to never post again.
So I started a local Facebook group. It's full. Loads of people posting all sorts of stuff. The upside is that the Facebook functionality encourages social interaction - less asking questions more chatting about stuff people have discovered or arranging to go out to a museum/bar/hike etc. The downside is that people outside the city don't join, so my events don't grab people from other cities as they would sometimes do before.
So now the forum is full of people who have been there for years, just having in-joke chats, or pushing their political views which haven't changed in years and hence are boring to read. The occasional newbie joins, doesn't understand what's going on, gets "use the search engine it's been asked before" as a (valid but terse) response to any questions and leaves.
Global forums like these are more likely to thrive, especially as tech forums tend to attract people who like to spell out their message rather than just post a picture of their phone and a turd emoji to garner likes.
My concern is that whilst younger (that me) people enjoy Facebook, soon there'll be an even younger set that'll be on something else and the Facebook groups will follow the forums' deaths. Except this time I'll be too old to work out where everyone's gone
