Who do you believe?
Who should I talk to about this?
Who does this car belong to?

These "scientists" will lead you to believe that whom is a better choice in the above sentences, but they can't point to any actual evidence to make that claim. Nobody uses whom anymore, nobody fucking cares about the distinction. If language can fall in and out of favor by culture, maybe its not a hard science and more of a social convention. I am almost 99% positive linguistics is a fake field and some type of money laundering scheme for communists.