I've just come from replying to your grandparent/grandchild analogy. And this is basically the same problem. You don't seem to understand that analogies need to be coherent and internally logical to be useful.

I can say there are parallels between any employment process and how slaves were appraised. Or even between dating and how slaves were appraised. Because, on a certain level, we're talking about appraising human beings for their potential value to us in some sense or other.

But in both of those cases, the comparison would be absolutely idiotic. Because it leaves out enormous context.

Yes, details do matter. Details like, for example, the fact that football players are paid millions of dollars. Or that they enter into their contracts freely and willingly. Or that they can leave at any time. Or that their families aren't forced to become football players too if they don't want to. Or that team owners don't rape the players' wives and mothers. On and on and on.

Drawing any comparison between the suffering of the slave trade and the lives of fame, luxury and plenty enjoyed by professional athletes is crass and ignorant almost beyond belief. I don't think you actually disagree with this. Which begs the question, why are you wasting both of our time trying to justify it?