Is Turkey even an ESA member? I don't think it's clear they'd be welcomed. This seems like a sensible way for them to dip their toes into having a space program.
A fun thing is, He is from the secular demographic and his firsts words were to commemorate Ataturk and the islamists and seculars instantly switched place; Now the pro-government people say He is a space tourist and the secular opposition says he is a hero :)
This is an understatement. He was purged from the military and jailed by Islamists/Gülenists/Erdoğan using fabricated evidence and cultist judges, for "attempting a secularist coup".
I don't think it is "essentially" for propaganda. This would happen regardless, propaganda is just a side-benefit. Saying that he's "just a space tourist" would be like calling scientists that go to Antarctica for experiments "polar tourists". It is definitely overblown by the government media though.