I agree, even most things that are proven to be definitely Iranian are subject to cultural theft by either pan-Arabists, and/or pan-Turanists. I suppose you read the compendium about pan-Turanism's legacy in Iran by Dr. Farrokh? So many things have been claimed out of Iranian hands. This includes algebra, the Shhnme, even the characters we know as Bbak Khurramdn and Cyrus The Great.
What hellenophiles tend to forget is that entirety of our pre-Islamic heritage covers only a fraction of Hellenic history altogether. This fraction is made up by a mix of Roman and Greek sources and also Islamic sources (Written by both Arabs and Islamized Iranians), who make a rather antagonistic portrayal.
Of course we showcase pride whenever we speak about the achievements of ancient cultures. What some absolute dolts just don't get is that everytime you got to a library, you'd have one hell of a luck if you could find anything but Olmstead, Clive Irving or Richard N. Frye, regarding Iran's history as opposed to books dedicated to the Greeks and the Romans. Perhaps we should attribute one of the greatest cultural genocides in history to Islam, as the adherents actively sought to destroy heretical (Actually they didn't care, they just had this giant book burning festival) literature and sciences. Oh noes, I speak too much about achievements..