But certain standard have to apply that are not met here.
First, the actual language of the law is very specific. Secondly, and most importantly, there is evidence that legislators considered adding the "missing" language. The general principles of statutory interpretation include that if language is ambiguous (which it isn't in this case anyway) and Congress considered a particular interpretation but explicitly did not include it, that they therefore meant to not include it and it should not be construed otherwise.
There is no way for a judge to rule that the "intent" is to provide a subsidy through a federal exchange, despite being in stark contrast to the actual language of the bill, without completely undermining the legal system. Oh, some will try, but I wonder if they realize how much damage they are doing to their own branch of the government in the pursuit of naked partisan politics.
To late for that, already been done. Roberts ruled the ACA was a tax in spite of the feds argument that it emphatically was not a tax, but a fee.