I do find out stuff from FM. I'd never heard of keeping your casters crispy in a pellet pump. I learned a lot about factors affecting fish stocks in rivers from some environmentally clued-up members. And so on. I'm sure there'll be more.
But I wouldn't say "knowledge" is the main reason for coming on here for me. If you've been fishing, talking to anglers and reading the angling press and books on fishing all your life, you don't come across new stuff all that often. But if it's some tackle item you want to know about, this is a mine of information. Conversely, it's quite nice when someone, possibly new/newer to fishing asks a question you can answer and you find some of the stuff you've accumulated over years is actually useful to someone else.
But there are lots of other things you can get. Read the angling weeklies and it looks like everyone is catching big bags and big fish. I like how our fishing reports ground things in the reality - sometimes we catch a lot, sometimes a little, sometimes nothing. Writing up a bit of a report to share on here is a nice way to round off a session and make something out of the day's experience. There have even been times when I'd probably have packed up, but the thought of having to post an embarrassingly small catch inspired me to try a bit harder to get something out of an unpromising day.
Over the three years I've been on here, I've been out fishing with five FM members, all enjoyably and some, when distances are not prohibitive, several times. It's great to widen the pool of people you can share your love of fishing with. I'm hoping to meet up with a couple more people when the river season opens.
Unless we do nothing but match fish, we must be attracted to some extent to spending time on our own, often in lonely places, and happy with our own company. More than information, the value of FM, for me, is it adds some social dimensions, real or virtual, to the sport.