In this case, age is not what disqualifies the law. Rather, what renders the law inapplicable to this situation is some combination of:

1. another statute that super-cedes the 1930 statute because it specifically limits Presidential emergency powers in the context of balance-of-trade issues. See around p. 35 of the slip opinion.

2. The Constitution itself, which limits Congress's ability to cede its own powers.

People love to say things like this, but much like electing an 80 year old president, it should perhaps be a trigger for a more thorough evaluation.

i don't think anyone would disagree that a law can "age out", but simply ignoring it because it's old versus revisiting it's intent and modifying/removing/etc are two very different strategies.

Unmodified law? The law in question has been amended many, many, many times in the last 100 years.

For goodness sake, the original law set specific tariffs for 20,000 different goods. Little of the original law still exists unmodified.