Yeah, but with how we’re moving towards running each (desktop) application in its own cgroup, thus restricting what syscalls any given application can do, soon any old user process will no longer be able to read any other process’s memory. I don’t believe that the argument about how we need not patch a hole because another one exists right besides it is sound.
I agree. My point was only that this hole can easily be patched in X as well. So the argument was essentially "we do not bother to patch it with X, so we must rewrite X".