30 here.
I started playing GT1 in 1998 along side my best friend.
He's since turned away from the GT series since GT4 and following GT5 due to the lack of customization and liveries we found in Tokyo Extreme Racer 3, NFS: Underground, and then finally the Forza series.
We were 14 when we started playing GT, and thinking about it, it has only really changed in car count and graphics. I've been good with GT's appearance since GT3, just really wanted some customization/liveries... You know?
Anyways, Got GT6 for the new Diablo's, VGT's, the new customization features with the promise that "More custom parts will also be added in future updates", the promised club racing, track creator, and new community features to come,
This may be the last GT I play depending on what they do from here on out and what new they announce for GT7.
But yeah, I've been playing GT for 16 years off & on I guess. With GT1, GT2, and GT3 being the most played (continued playing GT3 after GT4's release). GT4 coming next, GT5 afterwards as GT5 felt like GT3 with internet and more cars and tracks, and GT6 is GT4 with more cars & tracks.
Owned GT1 & GT2. Still own GT3, GT4, GT5P, GT5, & now GT6.