You continue to say "suffer", here, and I really think you'll find that, if that change was made, many people, especially younger people, and "cooler" people, would move away from those services, if they haven't already.
You misunderstand me; we're talking different (though overlapping) purposes for different platforms. I'm not talking about personal info; I'm talking about generic information. Right now, if you Google something (say something silly like "How do you pronounce drow?") the search results turn up forum threads. EN World is 4th on the front page of Google for that. That's how 90% of EN World's traffic arrives here - someone Googles for a piece of information, and it's in a forum thread. Your Facebook group doesn't appear. Same sort of thing if you Google how to fix the speaker on your iPhone or what folks think about a new washing powder. A forum becomes an information repository, whereas a scial network becomes a conversation. They start to diverge in function. That said, as I mentioned earlier, forum software companies are working hard to integrate the software with the social networks so forums themselves are changing in nature.