Turkey is more interested in crushing the Kurds than fighting ISIS, what do you expect?
As for the supposed ethnic cleansing by the YPG (a charge the Society for Threatened Peoples has refuted, for the record), don't you think that sounds a bit bizarre considering that Rojava's armed forces includes militias of just about every ethnic group in the region? Christians, Muslims and Druze, Assyrians, Armenians, Arabs, Kurds, Turkmen and Yazidis (who the YPG/YPJ/PKK rescued from genocide at the hands of ISIS), you name it. And a system of guaranteed political representation for all communities, at a decentralised level?