Contrary to cope from the creatures that infest
odern history academia, the late 19th century view of the Roman population (starting capable + homogenous, dysgenic decline and migration from the Middle East in the Imperial era) has been confirmed by genetics (many such cases).
As with so many other cases, if you just believed the historical sources, which talked at length about the novelty and severity of Middle Eastern mass migration and the decline of elite Roman bloodlines, you would have gotten this right.
I give mainstream history credit for things like events, battles, who did what, when, but today so much is just oceans of cope for why the sources are wrong (US Reconstruction history is another egregious example of this, Aryan Invasion + other prehistoric invasions are another).
Particularly funny when they point out that people have similar concerns today as evidence that migration and dysgenics weren't problems for the Romans (cf ACOUP). It's the other way around, obviously - these problems recur perennially through human history.
