Is Pokemon timeless, or has it never evolved?

One night, I did something and I still don't know why I did. I picked up Pokemon FireRed Version and inserted it into my DS and started playing. At first, I was a bit underwhelmed at the game, even though I'd had it since it came out. So much was missing and yet...something kept me playing. Soon enough, I was no longer aware of the missing Poketch and X and Y buttons. This was Pokemon, and I was loving it all over again. But it then made me think. If I can play a game made 7 years ago and play Pokemon Platinum and have the same amount of fun, has Pokemon evolved at all, or had Nintendo's charm lasted all these years?