If I were to create my own generational progression chart, I'd look at it like this:
1) Combat Sim, growing out of the original wargaming background. Location, line of sight, movement, attack, evasion, armor, etc. The basic fundamentals. Wargamers.
2) Setting Sim. Whether trying to replicate existing properties, such as Conan, or building new worlds, such as Greyhawk, the game grew from individual battles to an entire world that people wanted to recreate. Writers.
3) Detail Sim. So many things can happen! What is a hit point? How effective is your armor? How charming is the bard? What is a crit? Rolemaster crit tables! GURPS power lists. Battletech everything. Nerds.
4) Genre Sim. Computers are a thing, and started showing that they do the detail sim a lot better than books and charts. Quit making the humans do the hard work, and let them focus more on having fun playing the game. Atmosphere is the key. An expansion on Setting Sim. Call of Cthulhu, World of Darkness, Dark Sun, Shadowrun, Castle Falkenstein, etc. Theater kids.