Randomly deciding, "oh, we'll just reinterpret the existing language to mean something totally different, and is cool because times have changed..." is a totally different ballgame.
That sort of thinking violates the legitimacy of our legal system at the basest level. If words in a law, or in the Constitution don't mean anything and meanings can be changed on a whim, there is no solid ground for anything.
If you want to change the original intent, though, that's an amendment. That's why prohibition required an amendment, for example. The court couldn't (as they disingenuously do today) just say, "well, over here the Constitution says that the feds have the power to regulate interstate commerce. So sure, prohibition is fine because commerce."
Doesn't matter anymore, though -- the majority of people, whether liberal or conservative, don't really care about freedom or laws anymore, or what the Constitution actually says. They just want the government and the courts to decide their way, regardless of whether it is good jurisprudence.
The judicial system discovering new rights is not.
And that clause of the Constitution certainly was not used when the question of mandatory health insurance came before the court. I would actually like that policy if it were consistently applied. Instead it is applied when it is the means to meet the desired ends. And that means we are a nation ruled by men, not by laws.
The Bill of Rights even expressly notes that the rights enumerated do not cover all rights and cannot be expected to cover all rights, and that those rights not enumerated are not meant to somehow be lesser -
"The enumeration in the Constitution, of certain rights, shall not be construed to deny or disparage others retained by the people."