From Atari to SNES/Genesis, I was a graphics lover. The better the graphics, the more I liked the game. However, there was actually some merit to it back then, as better graphics generally meant more time was taken developing the game. I didn't have favorite genres back then, I played anything I could get my hands on. I liked anything with reasonably good graphics and responsive controls. My tastes didn't refine until the start of the N64/PS1 era where the video game world just sort of exploded from my perspective. This was also the time when we got our first real PC at our house. At this time I was still hanging over in the SNES generation mostly playing my copy of Sim City and Civilization on the SNES. I never tired of those two games, but other games that contended with them was Flashback, X-Men (Genesis), Rock n' Roll Racing, and Earthbound. At any rate, I soon got a PS1, a friend got an N64, and we now had a household gaming PC.
At this point in time 3D worlds were thrust into my view. It started when my friend got Mario 64 and Quest 64 and I was captivated. Then Tomb Raider amazed me further. Ocarina of Time as well as the many games that followed. 3D environments seriously amazed me. It seemed like virtual reality back then to me. However, I also saw entirely new ideas brought to the table with 'fake 3D'. PS1 was how I was introduced to the original Xcom. As well, the original Diablo. Isometric view became a thing on PCs at that time too. I got to play Civilization 2 on PC (which later came out on PS1). The original Sims was released on PC and while I didn't play it much, it was certainly an interesting concept for a game. Survival Horror showed up with Resident Evil and Silent Hill. Final Fantasy stole the spotlight with cutscenes and many other JRPGs really boomed like Legends of the Dragoon. Metal Gear Solid brought its own unique flavor to the table. Doom came out and was the first shooter I liked that didn't have a gun accessory. (I didn't play wolfenstein) Smash Brothers came out and pretty much dominated all the time between me and my group of friends. That generation was a chaotic ball of fun and my tastes still hadn't refined until the tail end.
As the PS2 generation crept in, I found myself playing games more by myself. (Everyone wanted to play Smash Brothers when we hung out.) Online wasn't yet a thing really despite the PS2/Xbox going on about something called a ethernet port. I found myself playing Civilization 2, Xcom, and Diablo. Then we upgraded our computer and Diablo 2 and Civilization 3 released and I spent a ridiculous amount of time playing them in my spare time. But this is also when I found my first MMO called Anarchy Online. Long Story short, 7 years where I played it, Civ 3, Tropico, Anno 1503, and Diablo 2 with a splash of my favorite PS1 games thrown in because I was broke and couldn't afford to stay current in the game industry. Luckily, I found a copy of Arcanum for like $5 in a bargain bin and that game made me toss Diablo 2 to the curb. Then I sorta fell out of MMOs other than occassional spurts on City of Heroes and some F2P ones.
At this point, I was a singleplayer gamer because all my gamer friends had all grown up and we all had lives too busy to play games with each other like we used to. We still did and do play games occassionally, but we all have preferred tastes nowadays. I have gravitated towards builder sims and strategy games. I havent cared for sidescrollers since the 2D days and platformers need to offer something besides platforming. I like action games like Uncharted, Batman Arkham, RDR, etc. However, I don't care for shooters and I need a decent story to accompany my action. I like RPGs because they tend to have the most interesting mechanics, but they also tend to drag out the gameplay with filler content too often. I like sandboxes, but tire of them way too easily. (Except Minecraft but I think that is because it is part builder sim)
So I gues you could say that my gaming habits refined over the years to a more specific taste. I still dabble in other genres but I always end up playing the same games over and over. It kind of sucks because my backlog keeps filling up, I keep buying new games I want to play, then I go play Civilization and Xcom and Tropico for another 100 hours a piece.