Pretty incredible that it's survived decades and multiple iterations of the game, and you can still pick it up and buy your trusty AK or M4 and play essentially the same game from decades ago.
for some reason valve doesn't release new versions of the game but instead chooses to radically change all aspects of the game and call it counterstrike(increment code+1)
i like the model, much better than call of duty randomly naming things differently even though the games are fundamentally the same with a fresh coat of graphics on top
I know you probably don't care about things like movement accel curves or hitbox sizes (which have changed drastically over the years) but just look at the deagle, possibly the most iconic weapon of the franchise. the weapon went largely unchanged between 1.6 and source, but is almost unrecognizable in csgo. you simply can't use it the same way you could in the older games; it has a completely different role.