I know this is tilting at windmills but I am extremely tired of seeing this "every culture had slavery" dismissal.
The atlantic slave trade had unique characteristics that make it quite distinct from what's happened during Rome or the Czars. It also was only a couple generations ago. The legacy of slavery remains a very real force across all the prior slave colonies in the Americas.
There's always been murderers, but we don't use that as a thought ending cliche to dismiss the idea that we should try to prevent murders. We don't ignore the unique horrors of someone like Jeffrey Dahmer just because other murders existed.
Symbols and terminology matter. No changing the terms won't by itself eliminate ongoing slavery in the world. But it does shift the window of how people view things.
In my generation, the purge of the f word and using gay as a pejorative was only a few years ahead of legal acceptance of gay marriage.
Changing the terms won't solve the problem, but it is moving in the right direction.