“Daniel 8:8. This he-goat was Alexander the Great. Who in 323 B.C. at about thirty-three years of age, and at the height of his power, died. His empire was divided to these four Generals, of which Cassander had Macedonia, Seleucus had Syria, Antigonus had Asia the less, and Ptolemeus had Egypt.”
You are correct absolutely. However some are inclined to see many prophecies repeat themselves, or have multiple fulfillments. Gabriel tells Daniel this prophecy was for the last days.
“many prophecies repeat themselves, or have multiple fulfillments.” God gives Daniel a foresight of the destruction of other kingdoms, which in their day were as powerful as that of Babylon. Daniel 8:1-14