Keep in mind he likes to point out onion domes in russia, while ignoring their use in ukraine and belarus. The onion dome originated from byzantine orthodox architecture which originated from ancient rome. Through the years all of rus morphed their style around the orthodox style, russia did slender onion domes, while ukraine did broader domes, the middle east started doing onion domes only after the byzantine empire, their early works looked nothing like modern mosques or palaces.
Given the byzantine empire was the continuation of the roman empire, and their influence went through europe asia and the middle east, it is no surprise they spread their designs everywhere. He however is convinced because people in the middle east use them it must be mongolian design brought to russia, while ignoring that onion domes were used almost 100 years before mongolia invaded that area, and that no mongolian architecture ever matched it until post invasion suggesting mongolians copied the style rather than supplying it.
Also keep in mind as far as christian anything, arabic aramaic and hebrew were very widely used in early christianity, which later fell apart when the catholic church pushed latin as it's sole acceptable language for the writings.
