So everything is patentable and it's judicial activism for the Supreme Court to rule that something is unpatentable? Why do you assume it works that way and not the other way around?
At no point have I used the word judicial activism, nor will you ever hear me use it, since judicial activism
is code for "judges doing their job". They can, if they see it in the law, set limits on patents. If there is nothing in the law supporting such limits, they would be hard pressed to add them randomly.
I was, unfortunately, being a bit pedantic earlier and nitpicking your terminology (expanding vs actually interpreting some initial limits) instead of debating your actual point; I apologize for that.