The only person I truly know about is me. I've quit many times. Always quietly. And I usually decline the "why did you leave" question. It's usually "I don't have time to play" or "my internet connection makes the game unplayable".
There's only one thing that has ever made me rage quit - cv puffy ack. I could do immediate evasives and the ack would still be exploding right in front of me. Those AI gunners are psychic! How do they know where I'm going. It takes a long time for puffy ack to get to 23k alt. How can it explode in front of you right after you pulled a high g turn with a major alt change to get away.
Lately, if I wonder into cv puffy ack in a TA152, I'm on fire after the first few pings.
I even lost a 262 at 23k alt to fire from cv puffy ack recently. That's right, "snap", oh crap I'm in cv ack, "crackle", "pop", and to the tower.