Those games are pretty mainstream, I can't imagine how many gamers are getting rooted as we speak. I'm glad ubisoft are getting their asses kicked over this (especially with their history of aggressive DRM'ing) but for the users that's terrible. So no, I don't think that's very responsible.

That being said, installing a "sudo" plugin in everybody's browser without any security validation (if I understand correctly what this is about) would be hilarious if it wasn't that tragic. But gamers are gamers, they forgave sony, they'll forgive ubisoft too, and they'll never learn.

If you could install a sudo plugin to my browser when I install your game would imply that I could have also installed a sudo plugin. If I (a non-root) user can do that, you already have a problem. (I am assuming you mean a sudo plugin that does not need a password to root)

You asked a very laden question. You have no doubt encountered discussions about full-disclosure to know the arguments against it; giving a one-sided rehash of that topic is a provocative way to invoke an old and tired discussion.