What you are missing is that your citations are little more that someone elses version of history, often slanted to promote a view. Kinda like what Texas has done to history books to promote American Exceptionalism or Trump proposing to only tell positive stories about American history, as if he knew anything about it. Here's some info about a Thomas Jefferson historian covering up the fact that Black teen slaves were beaten at the nailery to improve productivity. BTW, at the Monticello tour, they often mention Jefferson had 400 slaves there during his lifetime, omitting the other hundreds he owned at other locations. Yes there were some slaveowners who owned more than Jefferson but he was in the top twenty and only freed two during his lifetime, one of whom paid $200 for the privilege, after his death, most of his slaves were sold to pay off his massive death.

https://democracyguardian.com/edwin-betts-the-man-who-literally-changed-history-d5e9674ad6fd