There's a pretty compelling theory that the original wasn't destroyed at all, that the frame is an old magic trick, you roll the painting out of view, and spit a torn up half out the bottom. Did you see the photo Banksy posted of the x-acto blades ? It really is rather nonsensical... [0]

Then again, maybe he's playing the long game once people figure out the whole charade is Banksy selling out, the price of his work crashes, thus restoring its purity as self-expression.

[0] https://www.boredpanda.com/banksy-painting-girl-with-balloon...