Rome's Empire collapsed in 1453 though. That's a historical fact.
Rome was sacked in 410, 455 and 546. The WRE(capital: Ravenna) fell in 476. Something is missing, don't you think?
Yes I think the Roman Senate and Patrician class (relevant up to the last days), the city of Rome, and the Latin language are missing from this Byzantium-based Greek-speaking hereditary autocracy that you are trying to convince me shares continuity with the SPQR.
Your source for this "Historical Fact"?
Please, do yourself a favor, and read Gibbon's Decline and Fall and HG Wells Outline of History.