To take it further, it's like saying Microsoft should release no more Microsoft Updates for Windows because virus makers will lose interest in making viruses.
Although I enjoy your extended metaphors, I never said people should stop trying anything new. You're defending against attacks I'm not making.
[But to reply to your metaphor: I certainly hope you're not intending to compare Microsoft software favorably to Wikipedia contributions. I'd rather, if we were to use this analogy, strive for something like Linux, BSD, or OS X where massive gaping security flaws aren't inherent in the system.]
Massive gaping security flaws aren't inherent in Wikipedia in regards to preventing vandalism? That's news to me.