It's an education thing.
The current generation of forum users can't write more than a few words in broken English. They simply aren't cut out for life on a forum. Texting or Twitter is more their thing where they can get away with being illiterate.
My generation are generally better educated and find it easier to have a debate or discussion on an internet forum.
Oh quite right.
However I don't know if it simply generational.
I cringe when I go on facebook and see some of the things my "friends" are "liking" and commenting on. It is only through reading their (or "there" in their language) fabook rants, ramblings and status updates that I have truly realised how retarded some of my pals are.