When I first joined WP I'd see a thread appear from time-to-time in effect calling us Self-Diagnosed Aspies "Fakes". At first I was quite offended, but now I just tend to brush it off.
I am quite happy with my self-diagnosis and I'm certain in my own mind that I have AS. At the end of the day, what other people think doesn't change that. It's too much hassle to get a real diagnosis - tried once and the GP just poopooed the idea that someone of my age could have got so far without one.
I've managed to survive OK and, through luck rather than skill, I've done alright in life. I don't think a diagnosis would do anything for me now. When I was younger and struggling at school and uni and with family crises, then yes, it would have helped, but I'm through all that.