You might believe he did that. Brendan Eich likely doesn’t believe that, or he doesn’t believe those specific rights are fundamental, or he has a different interpretation of those rights.
When you frame his behavior the way you just did, you immediately position your perspective as right and the other perspective as wrong, but the parent’s point is that this isn’t relevant either way. His behavior was not expressed in the workplace, and he was not pushing a violent agenda. He doesn’t need to be correct in all of his personal views, he just needs to be capable of working with people of differing lifestyles, and he needs to segregate his own beliefs from the workplace.