
I mean he’s kind of right-ish. Islam did expand militarily westwards into the Roman Byzantine Empire (and parts of the Mediterranean like Southern Italy and the Iberian) and definitely persecuted Christians at certain points, but most communities were allowed to exist under special taxation or unequal legal status. I mean the claim they only stopped expanding westward due to Christian military resistance is partially true (see Reconquista and the Battle of Vienna). Overall exaggerated.
They portray it as a rivalry between the two when from my knowledge Islamic leaders were fine with Christians in their state as long as they paid their taxes before the 14th century (that’s where my experience ends). They have a common Abrahamic root and Muhammad lived in a diverse area among Jewish and Christian groups.