Plenty of people at that time recognized evil for what it is.
Yes, and many others didnt
slavery was a practice in virtually every society around the world
and older than any living American at the time
yes most white Americans looked down on black people as inferior
and if you look you can still find that attitude in China or Japan today
or India where darker Indians are looked down on by lighter Indians
old habits are habits to break, but America worked harder at it than almost anyplace else on earth
and this hate for American history coming from the left today is unjustified and harmful to every living American