Ah, I see. It is still weird IMO that zeke looks that old though. Could it be because of his titan powers? The previous owner of the coordinate seemed kinda sickly, perhaps for all its perks having titan powers reduces your lifespan...
Ah, yeah, they do have some cars.... We can safely assume they have 20 years worth of progress over that at least.
I don't think he looks
that old (could be the beard, but I mean not even Levi would seem like a guy to be well over his 30s, right?), but yeah the Titan powers could have something to do with it, or maybe only the Coordinate power - for some reason - does that to its holder, we have yet to see how other shifters are affected, though Kruger might shed some light on this, could be one of the reasons why he choses to pass it on to Grisha.
As for the Marley's development, there could also be a very small possibility that the Marley government doesn't exist anymore, thanks to Zeke, but we'll just have to wait and see. It would make some sense considering some stuff from the past, and that way the Scouting Legion wouldn't have to fight a whole continent in a war that they just couldn't win, so I think it makes kinda sense to remove the Marley from the equation, but I could be dead wrong.