If you think law has too much room for interpretation when we care about it says, what makes you think anything would improve if we instead cared only about what it meant to say?
The spirit of the law is important in American jurisprudence, but there’s a reason that no serious legal academic advocates for abandoning black-letter interpretation: a cornerstone of jurisprudence is predictability. In order to be justly bound by the law, a reasonable person must be able to understand its borders. This gives rise to principles in US law concerning vagueness (vague laws are void ab initio) and due process. We can’t always ascertain what the “spirit of the law” is, should be, or was intended to be, but we can always ascertain what the law is. Even in common law and case law, standards must be articulated, and the state must give effect to what is actually said, and not what it wishes had been said. Abandoning this principle in order to “close loopholes” is just inviting bad actors who currently exploit oversights to instead wield unbridled power against ordinary people who could never have even anticipated the danger.
That loopholes are left open deliberately is not a failure of legal interpretation. It’s a direct consequence of corruption and regulatory capture. Rewriting American jurisprudence won’t solve those problems. Hanging oil magnates and cheaply purchased bureaucrats will.