Critical Reasoning (CR) | Re: A law passed in Rockville three years ago allows a 30% tax

But conclusion says:Obviously, this law has had little or no effect on the sale of newly constructed homes . So, presence or absence of the law doesn't matter. Then why absence of the law would yield positive result i.e sales wouldn't drop significantly? According to D presence or absence of the law DOES matter that presence of the law generates negative consequence. What I am missing here?GMATNinja , your help would be much appreciated.
...

---