I'm surprised you queens never went for Constantinople.
Greece can't take Constantinople back because of America. Turkey is more strategically important and would support them in a second, that's why they turned a blind eye to the 1974 invasion of Cyprus
You didn't hear any of the Bushes complain about how Axis of evil the Turks are. Hell, most Americans don't even know about the invasion, but most know about Iraq's invasion of Kuwait.
Greece and Turkey are both NATO members so there's that too.
Pre NATO they were just too weak from occupation and civil war to reclaim anything.
Fun fact Greece still calls it Constantinople not Istanbul and they have a soccer team who's home is Constantinople but they play out of Athens haha