scads of casual programmers who have unwittingly written innumerable remote exploits
Very good point.
Part of why <> upsets me more is that the fix is obvious to me and I'm galled by people claiming that it isn't a problem and can't be fixed. My preference would be to immediately change the default behavior under the theory that it fixes more (by far) existing code than it breaks.
I also see real usefulness in the magical, 2-argument open. Which makes it harder for me to see how to fix the problems with it. And I try not to get upset over complex problems that I don't see clear, non-trade-off solutions for. There are just way too many of those in the world and I prefer not to spend so much of my time being upset.
But I can certainly appreciate where you are coming from now. (: