Especially in late-game pop space needs to be liberated for more military. Sadly, some villagers need to definitely stand aside.
It’s not necessarily easy and certainly not quick to know where all those lumberjacks/farmers are when your “base” is all over the map in late-game.
AoE III has THE answer, which AoE II lacks: you click on the number of vills gathering a particular resource, and the game focuses immediately on where those are.
AoE II should also get that feature.