Negative outcomes of the Trojan War?

Answer 1

While the Achaians returned home loaded with loot and slaves, and provided good tales for the bards to entertain people with, they faced a weakened homefront. Peoples were on the move into their territory, and Greece entered a Dark Age for half a millennium.

The littoral cities of Asia Minor were also devastated by the 10-year looting spree. The area came back to life only by the Greeks sending their growing excess population to form colonies on the coast of Asia Minor and the Black Sea.

And these overseas Greeks became a perpetual problem, as various empires expanded into Asia Minor - the mainland Greeks supported the Greek cities there, which embroiled them with problems from first Persia, and then much later the Ottoman Empire.

It was eventually resolved after World War 1 in 1923 CE when the Greek population was evacuated to mainland Greece. The Spartans had suggested this solution in 479 BCE after the Xerxes invasion was repulsed - 2,400 years earlier, but it was not taken up.