I’m replying from my phone but I’ll try to provide a coherent reply. I will ignore all the “getting better” parts because purely based on your posts, I am not the one to tell you or anyone else on the forum what makes you a better player since progress of members of this community is insane.
I must admit that I was actually shocked when I read this post. And not because I think that everyone should be a performer or that there’s something wrong with anyone who just enjoys playing for themselves in the afternoons, just to relax after work/school. I was shocked because playing live was my modus operandi since the inception and I guess it is the first time, I ever heard (well…read I guess) anyone express this directly.
This will sound a bit “wishy washy” but even as a kid I felt that the music is the closest to transcendental feeling one can get to (well as a kid, I’d use less fancy words haha). Concerts are a place where your personal views and the views of the people around you don’t matter. I mean they matter, you don’t lose your identity but it shows you that there is something that connects you to the other person in a joyful, happy and meaningful way. So far I’ve only experienced this in live musical settings. And because I know you’re studying Justin’s PMT: There would be no harmony without different voices. (And life would be boring.)
I formed a band within a year of playing, I jammed on stage a few months later. I love music and I love people. I have a hard time writing songs on my own but the moment you put me either in a band or on stage, ideas start to flow and energy bounces around between me and other people. I know this can be done in a private setting (a k.a. band rehearsal only without a gig), but the moment you include the audience factor, you get this 110% version of yourself that is more in tune with yourself/your thoughts/your emotions → better, more honest ideas flow.
To touch on your point on why/how to go. I go to 95% of gigs (from open mics, busking sessions to stadium gigs) alone. I am there for the music and I’m happy just to perform my two/three songs and then listen for the rest of the night. If I do it regularly or if others are there mainly for the music, I’ll eventually get to know someone (but that’s not why I’m there). Heck, I’ve met one of my closest friends and guitarist in my first serious band waiting in the queue for a gig!
Lieven mentioned the 16 personality types. According to the test, I’m extroverted (which I agree with) but I’m a relatively reserved and quiet person who puts a lot of thought (probably way too much lol) in what I say. Therefore I either have long conversations with people or no conversation at all because I’m just not capable of putting my thoughts in short sentences (also one of the reasons why I’m mainly a lurker on this forum). But give an instrument (doesn’t really matter which one) in my hands and an audience in front of me and I’ll get my thoughts across easily.
Lastly, a bit of a silly answer but it makes sense in my mind. You’re a player. You go to an open mic. You enjoy music there so let’s say it provides you a few hours of good time/entertainment for free. Isn’t it a nice way to pay it forward to sign up for it and provide good time to someone else. Justin teaches you, you pay it forward by being super helpful on the forum. What’s the difference with an in person open mic. Or if you want to finish on a philosophical note: music brings you joy, why not share it with others :)?
EDIT: Well, that’s a long reply for someone who can barely use a touchscreen. No wonder it took ages to type lol