I am sure I have lost viewers because of an opinion, view, message or such that the update conveyed. You can't please everyone and some people find it hard to continue reading something that clashes too much with their views. Or it could just be that the story is not their type and the update was merely a confirmation that things won't change the way they hope. Or the scene was just too much for them.
You can't please everyone and while is depressing the lose a subscriber, you have to take it gracefully because leaving quietly is the most polite thing to do and the right to do when someone doesn't like your work. We do it too so of course will too. And that's ok.