Turkey during the 1920s and 1930s underwent a radical break from centuries of Ottoman tradition. The Kemalist government sought to construct a new Turkish identity independent from the Ottoman-Sunni tradition... something which had been totally nonexistent prior to World War 1.

Clive Foss' 2014 article "Kemal Atatürk: Giving a New Nation a New History" doesn't go into the suppression of traditional music, but is a good rundown of the cultural-revolutionary policies brought forward by Kemalists in Turkey's first decades.

With the abolition of the caliphate, the closing of religious schools and the introduction of new law codes from Europe, the state and its educational system were being secularized. Turks now lived under the Gregorian calendar rather than the Islamic, and were obliged to adopt western dress. They were increasingly cut off from a past that Kemal considered an impediment to progress. Most importantly for culture, he promulgated and personally taught a new Latin alphabet to replace the traditional Arabic script; from 1929, its use was compulsory. This meant that new books on every subject had to be produced, and that the generation entering school would no longer be able to read the old texts. Kemal was especially interested in history, which could provide a context for his reforms and strengthen the self-image of the republic.

Education was central to establish this new Turkish identity, which is why the older, Ottoman systems had to be destroyed.

The Ministry of Education was in control, closing the religious schools and imposing a unified system with standard textbooks that would reflect the ideals of the state. No others would be allowed. A new basic text, simply called History, was written for the secondary schools which offered the highest education generally available at a time when only a tiny minority went on to university. Simplified versions were produced for the middle schools. These volumes would provide the only understanding of the past that rising generations would have. They responded to what Kemal felt were two great needs: to show that the Turks were and always had been a civilized nation, worthy of being considered equals of the West; and to prove that the Turks had priority in their Anatolian homeland, pre-empting the claims of Greeks, Armenians or anyone else. They are very valuable for understanding the mentality of the times, at the height of Ataturk’s reforms.

Turkey today is still grappling with the outcome of the Turkish revolution, and the increasing power of Islamists and Neo-Ottoman politicians like Erdogan suggests that the attempts to replace the Sunni Ottoman identity with a secular Turkish identity were only partially successful.