I'd say, from my experience at least, that you stop caring when you've got something else on your mind. When fandom isn't in your life 90% like it was, or even 50%. At the moment, although I have a drarry fic I want to finish, the main focus of my thinking and my worry is the decision to self-publish a romance novel. Will I finish writing it? Will I be able to afford a good cover? Will anyone read it? Competitiveness is still there, but it involves the (future) professional sphere, so worrying about who recced my fic seems silly (not that it's silly for people to feel that way; I did for a long time. It's just the way it feels to me now).