A muslim country joining the EU is a pipe dream. The days of Ottoman rule are hardly forgotten in the Balkans. There is zero chance you'd have Turkey, countries from former Yugoslavia, Bulgaria, Romania, not to mention Greece and Hungary in the same union. Just having Greece and Turkey in the EU is a laughable prospect.
Having France and Germany in the EU was a laughable prospect in 1945. Having eastern European countries in the EU was a laughable prospect in 1989. Circumstances change.
Well yes, that's why the EU was created. War with France was merely a distraction to create an united Germany:
Erdogan and those closest to him are not religious fanatics. Religion is just a tool for them to gain and consolidate power.
Maybe not fanatic, but a bit weird?
"One cannot be secular and a Muslim."
"If the skies and the ground were to open against us. If floods and volcanoes were to burst, We will not turn from our mission. My reference is Islam."
"Our minarets are our bayonets, Our domes are our helmets, Our mosques are our barracks."
I've read a fair share of articles about his rise and background and was left with the impression that he always has been rather religiously conservative. But maybe that's the wrong conclusion. On the other hand, how can you be sure? It is hard to know whether someone is a religious fanatic or just uses it as a tool.
However, since no one can replay history, no one can be sure that this actually would have happened. Erdogan would still have been himself, with the same corrupt attitude and religiously fanatic mind.