Super Smash Bros. Brawl
I still get hyped for games, but I don't think that can ever happen again. I was just the right age (the entire hype cycle took place over the course of middle school for me), and it was just in that period of the internet where people weren't quite cynical about everything yet. Though the rollout for that game is still unmatched to this day, and that's something that could definitely be recreated. The Sakurai blog and the way it was handled were all genius. I'd wake up every morning and check that. There were so many crazy discussions people had, and every day I had no idea what I was going to expect.
As for how I feel about Brawl itself, at release it completely met expectations and I was pretty blown away. All the content, characters, SSE was basically fan service perfected. I never put time into it like I did Melee past the initial first couple months (though I played it A LOT then) since once I got into high school my buddies I spent all that countless time playing SSBM with either had busier lives (though we still found time to play once every couple months) or just didn't really fuck with Nintendo anymore.Then I downloaded Project M in like 2012 and I don't think I touched vanilla Brawl for some time after that.
In 2014 I got into the Melee competitive scene, I went back and played Brawl just once at some point a few months afterwards and it was.....crushing. All of those flaws everyone had talked about online were suddenly immediately apparent to me. It's a slow, clunky game with movement that just feels wrong. The balance is awful to anyone who bothers to spend a minute looking up information about chaingrabs or any of the crazy shit Meta Knight can do. Even though I was just a casual back then, I don't know how the degree to which the movement just feels WRONG didn't ever occur to me. I still stand by it being an amazing piece of Nintendo fan service, and I still think SSE and the single-player content are cool, but just as a pure game I'd rather play every other Smash game.