you can't have everything

Both lived in Persia. Persia became Iran. Both are Iranian :trollface:

Yes, but actually Persia was the name given by Alexander, Iran was always called Iran, or rather, Aran.
In 1931, Reza Shah Pahlavi requested the League of Nations refer to it by its proper name, Iran, as it had been calling itself instead of "Persia" as other countries did.

Gee, maybe he wrote in his language because that was his language because that was the language of his people?

Just because someone spent a good part of his life somewhere doesn't mean they get to claim him as one of them because he's the only historically significant person remembered that resided in their lands other than Süleyman.