This is constitutionally false – it is not true.

African-descent people born into slavery in America were specifically codified as three-fifths of a citizen. They were not excluded from birthright citizenship by the Constitution. The 13th and 14th Amendments only ended their chattel slavery and promised them the rights of their birthright citizenship.

"From the nation’s founding, African Americans regarded themselves as citizens. When the U.S. Constitution was ratified in 1788, it did not restrict citizenship based on race. However, it only counted enslaved people as 3/5ths of a person, rather than as full citizens, in state populations." https://nmaahc.si.edu/explore/exhibitions/reconstruction/citizenship

That fact of their birthright citizenship makes their enslavement so much worse… it makes chattle slavery of African-descent people born in America something their fellow Americans did to them and allowed to be done to them.