Golden Age? I guess after the Video Game Crash of 1983. Definitely around 4th - 5th Generation, basically, the 90s. Not because it was my childhood(a little bit though), but IMO, it's definitely because of the transition of 2D graphics to 3D. We went from 16-bit to 32-bit, to 64-bit(Srz, Nintendo 64) in just less than a decade. Sure, it's chunky-looking, and I have heard and watched teenagers these days criticize the graphics, but they will not know the joy and awe of playing games that was in three dimensions. Like they always say "The graphics can't get any better than this." I've played NES, and SNES(relics of my dad still playing video games) first than N64 and PS1 btw. Other than that, IIRC the 90s was also the time when home gaming was on the rise. Less kids and young adults were in arcades(atleast where I was), and a lot of people were buying consoles and PCs.
There weren't a lot of games in 5th gen in the earlier years that can utilize 3D well, until only around the late 90s to 2000s. Megaman Legends were one of the few games that can utilize 3D graphics in a 360 degree environment. If we're talking about the generation when the use of 3D has been greatly improved, then as CyberAngel said, it would be the 6th Generation. Now graphics and the use of 3D movement in the PS2 era was phenomenally improved, Dark Cloud 2 and Shenmue are probably my favorite game(s) from that era.
After that, yes, it seems like graphics are the only thing(s) improving from there on out. I mean, I'm not surprised, and not disappointed at all. Since 1.) We've utilize 3D already, basically we're trying to mimic real life, I don't think it can get any better than that, other than gameplay uniqueness, or trying to make a game really like real life via physics, etc.(eg. GTA V), and 2.) I'm an RPG fanatic, and if I already have the joy of playing 2D RPGs and exploring 2D worlds, I would be more so exploring 3D worlds. I mean imagining is fun, but tbh, I'd be more enjoyed when I am actually seeing what kind of world I'm exploring. That's why I'm always hyped for games like Star Ocean, and I can't definitely wait the day when I play open-galaxy games(Star Citizen plox).