Except that tieflings are also from the hells and are not by nature evil - as seen very easily in BG3 with Karlach.
Tieflings are not from The Hells. They are mortals with a Fiend several generations back in their family tree. They almost all grow up on the Material Plane.
Paladins are likely to look down on them and be suspicious of them, like most people in Faerun, but they're not going to go around murdering them. Well, some are. The sort that take a stance that no corruption however small can be permitted. The sort that are the absolute classic example of the Falling Paladin.
