And remember Greeks were only 50% of the population of Greece at the time, most cities were majority Turkish or Albanian aswell as a significant amount of converts. It took outright genocide to win:
>"Women, wounded with musketballs and sabre-cuts, rushed to the sea, seeking to escape, and were deliberately shot. Mothers robbed of their clothes, with infants in their arms plunged into the sea to conceal themselves from shame, and they were them made a mark for inhuman riflemen. Greeks seized infants from their mother's breasts and dashed them against rocks. Children, three and four years old, were hurled living into the sea and left to drown. When the massacre was ended, the dead bodies washed ashore, or piled on the beach, threatened to cause a pestilence..."
Siege of Navarino
>For three days the miserable inhabitants were given over to lust and cruelty of a mob of savages. Neither sex nor age was spared. Women and children were tortured before being put to death. So great was the slaughter that Kolokotronis himself says that, from the gate to the citadel his horse’s hoofs never touched the ground. His path of triumph was carpeted with corpses. At the end of two days, the wretched remnant of the Mussulmans were deliberately collected, to the number of some two thousand souls, of every age and sex, but principally women and children, were led out to a ravine in the neighboring mountains and there butchered like cattle.
Siege of Tripolitsa
>The Hydriots murdered them all in cold blood, helpless old men, ladies of rank, beautiful slaves, and little children were butchered like cattle. The venerable old man [Sheikh-ul-Islam], whose crime had been an excess of zeal on behalf of the Greeks, was forced to see his family outraged and murdered before his eyes
Hydra Island
>But the most deliberate act of extermination was that perpetrated at Eteà. In this small village, too, the Moslem inhabitants, including the women and children, had taken refuge in the mosque, which the men defended for a while. The building itself is a solid structure, but the door of the small walled enclosure... was finally blown in, and the defenders laid down their arms, understanding, it would appear, that their lives were to be spared. Men, women and children, they were all led forth to the church of St. Sophia, which lies on a hill about half an hour above the village, and then and there dispatched—the men cut to pieces, the women and children shot. A young girl who had fainted, and was left for dead, alone lived to tell the tale.[7]
Lasithi massacre, Crete.
>The Turks of Greece left few traces. They disappeared suddenly and finally in the spring of 1821 unmourned and unnoticed by the rest of the world....It was hard to believe then that Greece once contained a large population of Turkish descent, living in small communities all over the country, prosperous farmers, merchants, and officials, whose families had known no other home for hundreds of years...They were killed deliberately, without qualm or scruple, and there was no regrets either then or later.