It must be stopped because it doesn't increase the number of green cards issued, it just reallocates them. As such, it will damage the existing system, rather

It must be stopped because it doesn't increase the number of green cards issued, it just reallocates them. As such, it will damage the existing system, rather than just creating a new damaged system. To build on your analogy, it's like burning half of an incomplete work of art, to get wall space for another one.