My first time in Mykonos was in 1983. I was 23. Gorgeous island, already crowded (it was September), very gay (but of course not EXCLUSIVELY gay), and I had an amazing time. Super Paradise beach was definitely 95% gay, too crowded for my taste. I will never forget how beautiful was Elia beach, very gay but quiet and unspoiled. And still there were basically pristine beaches (Panormos). The town was very crowded at night with lots of gay men, but fun, and still you could find restaurants and hotels VERY cheap even for me who was vacationing from Italy.
I went back twice once in June 2000 (it was still beautiful even if it had changed) and last time in 2010, when with horror I realized what Elia beach had become, with disco music, pool, beach club and the whole thing. And of course it had become an expensive place.
Never again. I prefer to keep my old beautiful memory.