It's ridiculous because names are mostly for the benefit of other people, and unfortunately society isn't so tolerant that everyone will accept it. If you call your daughter Titan Invictus you're going to have her go through life with people trying to stifle a laugh when they hear her name, or asking "Sorry?" or coming back home and telling their spouse about the kid with the absurd name in the class they're teaching.
People are also unlikely to change their name, firstly since it's their name that they've had for years before being old enough to realise that people think it sounds stupid, and secondly because they worry about hurting their parents' feelings.