Big nothing burger.
If the Patriarch of Constantinople professed the Reformed faith he would have to step down.
Bartholomew Calvin I would be an odd name for a patriarch...
Apples and oranges. Hanegraaff is not an ordained bishop in a protestant church leading the organization.
He is a lay Christian hosting a television show discussing passages found in the bible.
If a lay Orthodox Christian was hosting a television show that discussed the lives of the apostles, I wouldn't demand he step down because the show's host has joined the Church of the Nazarene. Pretty sure they can discuss the lives of the apostles too.
“If the Patriarch of Constantinople professed the Reformed faith he would have to step down.”
Um, well... https://en.wikipedia.org/wiki/Cyril_Lucaris#Calvinism