Kurdistan is understood to be a region rather than a nation state; just like Palestine has been for centuries. Kurdistan never was a country, nor will be. Palestine was never a country, nor will be. The main difference between the ideas of a Kurdistan and a Palestine is that Kurds are a real, and distinct ethnic group which lived in the Middle East long before any Arab presence in the region, while Palestinians are comprised of many types of Arabs and other ethnic groups which assimilated into the region and even included ethnic groups such as Jews. To be fair, there should be a Kurdistan before a Palestine is created.
from the article: Telling the story of Aramaic-speaking farmers in the Jordan Valley