The feeling is mutual Kainsbro. Most everyone who has experienced the pixelated era from the early odyssey and atari to the snes/genesis/turbografix, have at least once in their lifetime, played through the games in each of those systems. Not everyone who played retro systems necessarily prefers older games over the latest stuff, in this case the opposite proves true.
Most likely why many people still go back to older system games is because of how immersive they were at the time, not necessarily nostalgia, but the gameplay in those games leave a lot of imagination to the player and drew the player into the world of each game with the level design, what you were able to do with your game character, and what the game system allowed you to do in that era.
I would say that the reason behind this immersion is because of the feel of those old system games have that draw many players into playing the games we refer today as classic. I, myself still experience this a lot, and I remember the enjoyment I have with a particular game title and I discover newer titles from older systems along the way reading into them and experiencing the world they provide.
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