Welcome to RPGfix!
16 years, at least. Started on a Harry Potter Fanfiction Roleplay site (which I should tell you I knew nothing about it because I never read any...
This feels like a chicken or egg sort of philsophical debate.
I would suggest proboards too. I've used vbulletin and Enjin (which has a nice little mobile app but otherwise is dated in comparison).
Dropping in to say and introduce myself. Been writing since I can remember. It's a passion pastime of mine as is collaborating with other writers.