The U.S. Constitution DOES evolve and change and grow over time. It has done so, so far, 27 different times. There is a defined process for amending the Constitution, and, if we really want something in there unambiguously, we should follow the process to GET it in there.

The amendment process is long and difficult, and rightfully so; it ensures that only measures that have a broad base of support across the entire nation can actually be "set in stone" in the Constitution. Even so, one amendment that was a fundamental mistake (the Eighteenth, Prohibition) had to be canceled out (by the Twenty-First).

I don't think that "originalists" want to just ignore the Amendments when viewing what the Constitution says; it's the Constitution AS AMENDED that controls. Those Amendments are just as much part of the Constitution as if they were written there in the first place. Any language that the Amendments explicitly contradict (such as the infamous Three-Fifths Compromise) is effectively "struck out" from the original document.

But this is the important thing to remember:

“The Constitution is the supreme law, the foundation for all other law. If it doesn’t mean exactly what its text says—the public meanings of the words as ordinary people understand them—then no one can possibly know what it means. But if no one can know what the Constitution means, then no one can know whether any other law conforms to it. At that point, all that matters is the will of whoever’s in power. And that’s an exact definition of tyranny.” (Francis W. Porretto, "Shadow of a Sword")