I was 12 when I first played Wild World (on emulator) when a close friend introduced me to it, but I didn't like it much until I played WW on an actual DS when I was 15, so I consider 15 to be the first time I played Animal Crossing.
I think under 9- my siblings had it on the GCN, and I'd play it sometimes... and for whatever reason, my house was full of 8-ball tees. I still can't explain why I did it.
I actually found the receipt from Circuit City for AC on the Gamecube and it dated back to December of 2002. I would have been 11 at the time of buying. I remember being so excited to buy it after seeing ads on TV and reading about it for months on Nintendo Power magazine. Every month, there was always an article on Animal Crossing for future events that will happen and such. It felt way ahead of its time since it was "the game that keeps playing even if you aren't" and since no other game did this at the time, it made the game feel even more special.
I had a chance to play the GameCube version way back when but I thought it was an online game, meaning you had to get extra stuff for it. I think I was 18 at the time.
Then much later, I was at the store and had some extra money and saw New Horizons on the shelf. I decided to buy it because it seemed pretty popular. This was in March of 2022 and I was 38.
You know what, I feel like I was missing out on this series the whole time. It's fun just hanging out with your animal neighbors and fishing and whatever. I'm not in constant danger and I don't have to save the world or anything. It's different from the usual games that I play.
Reading through this thread I can't help but think I may have known some of your parents back when I was playing WW as I remember a few of them getting their five-year-olds their own DS and game so they could play in peace.
I got introduced to GC before 2010 so I know I was in my forties at the time because someone much younger than I had a copy of it and thought it 'too immature' for them to play. We got a kick out of it and I've played every version since. I didn't even know NH was a thing until a couple of years later when I found out two of my kids had it and were afraid to tell me because they knew I'd want it. I tracked down a used Switch, bought the game, then got a good amount into it when we had a traumatic time and had to put anything like that on hold. After the 3.0 update I thought it'd be a good time to pick it up again, and here I am.