The game worst based off of sprites, so…“gravity” isn’t even a thing here. What do you mean catapults aren’t affected by gravity? The sprites fly in an arc. Gates will not be in the game, and AoE:DE will have AI improvements, so walls might get used a bit?
Gates are invented in middle age, in the ancient age there’s only a space between walls and you can enter with your army to attack the city. The siege weapons are only for fun and free destruction. Hahahahahaha