It became so socially unacceptable that its proponents won the US presidency and took control of Congress and globally famous business leaders are bending the knee to them without repercussion? What definition of "can absolutely" are you using?
I personally did not read the parent comment's saying of "can" as meaning "has been"
The popular vote does not determine what is right. The US elected an incredibly racist Richard Nixon by a Landslide in 1972, but that doesn't mean society couldn't make progress on making it unacceptable to use racial slurs in public.
It is less socially acceptable in some cultures, more in others.
The fact that a gradient exists is proof that, under different circumstances, the social acceptableness of hatred can change.