Sorry Jimmy, his friend may not be right, but I don’t think he is wrong. Perspective plays a big part. Funny that when you say “The west spoke Latin and the east spoke Greek and Syriac and a few other languages.” you rather sound more like a Westernener in lumping everyone East of Rome as an “Easterner”… “Greek and Syriac” or “Greek or Syriac”? We aren’t a monolithic easy to define “non-Latin” catch all.
When looking at it through the lense of the Imperium, it would be easy enough to make this “East West” divide. But the question comes up here: What are the definitions of East & West being used by the folks who are having a discussion?
Short answer: We need more info, or to offer a more comprehensive and nuanced answer as the term(s) “East & West” are not set in stone and have multiple connotations. A Maronite, for example, once referred to me as being “Roman” from the standpoint that to him, Byzantines ARE Westerners.