First of all, all lives don’t matter. Not in the context they are using it in
Do convicted child molesters lives matter? Did Hitler’s life matter? Stalin’s?
Yes they mattered in a horrible way to the ones they destroyed. And I’m sure Hitler and all his cronies matter to themselves.
But that’s not what these people are talking about. They are saying every human being should be cherished. That’s nice in a fantasy world. It’s not real.