Once the secret of the location is known, finding the air supply and cutting it off makes these places indefensible. The Turks were just way better fighters, period. They mopped the floor with everyone they met until the sea Battle of Lepanto (1571) and the siege (1529) and land Battle of Vienna (1683).
I think the Eastern Roman Empire could've held them off though, but for the neglect of the frontier defenses and the army in general in the 11th century.
In the 12th century, the Comneni emperors recovered a lot of Anatolia, and maybe could've gotten back to the old Taurus/Anti-Taurus defense line if Manuel had concentrated there instead of Europe.
I guess that depends on whether you classify Tamerlane as a Turk. He gave the Ottomans a terrifc beating around 1400.
And what is not given much credit, the Persians tied down the Ottomans in a series of costly wars in the 16th and 17th centuries, which took pressure off Europe.
Not true. The emperor who lost at Manzikert to the Seljuk Turks had defeated them in combat twice before. The difference is in cost of soldiers. It cost a fortune for the empire and a loss was not easily recoverable especially for a diminished population of people living in cities ravaged by the plague.