I don’t disagree with this line of thought for the most part. I also admit to being biased as I’m very intrigued by the Bektashi in Albania. I feel out of any early modern Muslim group in the Balkans they’d have the best chance of integrating with a Christian majority country. But just because they have the best chance doesn’t mean it’s going to happen. Or at least happen in Greece. I just happen to like Greeks and the Bektashi and would love for the groups to work together.Personally, I find the Bektashi Albanians as a fascinating and interesting culture. Frankly, we should know more about them.
But when we talk about alternate history we should take into account how people viewed each other at the period we examine. In the case of bektashi Tosk Albanians, they were called Turkalbanians (Turkalvanoi, Τουρκαλβανοί) by the Greeks of the 19th century - even before the POD. The same applies to the rest of the muslim Albanians. Another name for a muslim Albanian was "Turk".
That applies to the whole region, not just Epirus and Albania. For example, when we read about the battles of Greeks with Lalas Albanians in the Peloponnese, we never read about "muslim Albanians" or just "Albanians" in contemporary sources. We read about "Turks" and "Turkalbanians".
To change contemporary attitudes we need a POD before the 19th century. This is why I was very sceptical about the revolting christian peasants in Epirus allowing the Chams to hold their lands in Thesprotia.
Indeed there was an umbrella of hellenism in OTL. So, there were groups such as the "Albanianvlachs" (Arvanitovlachoi. Αρβανιτόβλαχοι) that spoke tosk albanian and aromanian. They were included in that hellenic identity. But what 19th century people thoughts as "Turks" or "Turkalbanians" are not such a group.
The only thing I will disagree with is the implication that the Greeks are stuck with the OTL view of the “Turkalbanian”. Even if many of the Albanian Muslims leave Northern Epirus some will stay. I expect the intellectuals of Greece to try and write the Cham into the Hellenistic Umbrella, at least those that stayed. The view can and likely will change. Maybe not quickly or enough for a full scale Bektashi/Greece joining but enough that I expect the view of Albanian to be significantly more nuanced.