The commerce clause in particular has been used to justify most anything, including laws around production of your own goods because that can function as an alternative to interstate commerce.

But strict constructionism isn't an answer either. We shouldn't only have a right to bear 18th century arms, or let computer files be searched without a warrant merely because they aren't on paper. It's always going to be subjective, applying the law to questions that didn't even exist back when it was written. We have to do it, but we have to be more careful about it than we have.