Feeling firmly in the middle in all this age talk...
I'm old enough to remember the Smash Dojo and have some awareness of the Brawl speculation cycle. I remember that Snake being announced was a big deal but didn't really appreciate the full scale of it. I also remember Isaac and Geno getting a load of requests. And I fully remember going on the Dojo and being hyped as **** when I found out Olimar was in. However I don't really count myself as being a part of that speculation cycle, as I was too young to be going on any of the forums (okay, 12-14 isn't too young, but I was kind of internet-shy as a teenager lol). Nevertheless, Brawl fundamentally shaped the way I saw fan requests (Geno was always 'that Smash guy' in my head).
Had no involvement in the Smash 4 cycle, though, as my interest in Nintendo was at its lowest back then. I was busy with university and had no interest in getting a Wii U - I only got Smash 4 3ds quite late into it's life. In retrospect, I'm glad I wasn't part of Smash 4's hype cycle as it sounds kind of stressful. If I had been, though, at least I could have voted for Skull Kid in the ballot ...
While Ultimate's cycle hasn't been ideal, at least it's been much shorter than the others.
Born too late for Smash 64
Born too early to see Waluigi in Smash
Born just in time for Ultimate baybeeee