Anybody play Humankind?
I haven't, but I REALLY like the idea of cultures upgrading into other cultures. There's a problem in any game that spans a very long timespan in that you wind up with a weird mishmash of things like American hoplites fighting the Persians or Babylonians dropping nukes on the Japanese, which you wouldn't get in an RTS like Age of Empires (focused on a narrower timeframe).
The idea that you upgrade your culture into another culture makes a ton of sense, so you can play as something like the Celts and evolve into the British and then evolve into the Americans, or play Romans and evolve into Portuguese and then into Brazilians, etc.
There's a separate problem I've never really seen anybody deal with, though, where these 4X games (and 4X-RTS hybrids like Rise of Nations) want to include Native American civilizations, but they never escaped the Stone Age. So you get weirdness where you can play the Iroquois with their special buildings and units and all that, but they're still on equal footing with other powers. If I were designing a game like that (I really wish somebody would make a spiritual successor to Rise of Nations) I would have it be that the ages correspond to technological/development level for the society instead of just meaning "this is what they were at this time for Europeans."
The civilizations list also looks wonderful. Civilization games lately seem to have lots of stupid shit in them (crappy meme civs like the Cree and Australians) but Humankind has all kinds of wonderful interesting cultures that you just never see in these sort of games, like the Mississippians and the Garamantes.