Well, it's certainly not secure if you turn it off. I don't think anybody is under that illusion. But the issue you're taking here is that the status quo remains: if you do something your OS doesn't support, your OS vendor isn't going to support you. You're still free to do it, and can even do it securely - though it will require more effort from you. If you choose to disable security features instead of putting that effort in, you'll not be able to take advantage of the added security.