A major reason, and perhaps the most important one, is that the Ottomans never claimed that their empire was the Roman Empire. They claimed they had conquered t

A major reason, and perhaps the most important one, is that the Ottomans never claimed that their empire was the Roman Empire. They claimed they had conquered the Roman Empire and annexed it into their empire. The Ottoman Sultan had many titles, and some of them were considered more important than "Caesar of Rome". They were the Sultan of Sultans, the Khan of Khans, and the Caliph first. They also considered Mecca, Medina, and Jerusalem their most important possessions, and the Roman Empire only came after those.