Why is Thomas Jefferson's view on slavery considered controversial

Well, Thomas Jefferson was the person who wrote "all men are created equal" yet enslaved hundreds of people over his life. He also publically said that White people are superior to Black people. So I think it's safe to say his view on slavery would get him publically crucified today. Granted he did attempt to end any importation of enslaved Africans at one point in his life, under his watch, the act of slavery did not go down, rather went up. He also profited in many ways through slavery.

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explanation:

the second significant cause of the great migration was the desire of black southerners to escape segregation, known euphemistically as jim crow. rural african american southerners believed that segregation - and racism and prejudice against blacks - was significantly less intense in the north.