"We are under a Constitution, but the Constitution is what the judges say it is." NY Governor Charles Evans Hughes, 1907.
No English sentence is without ambiguity in its meaning. If a controversy over meaning arises on a matter as important as law, we cannot function as a nation on the basis of, "Aw, everyone knows what they meant...".
Whether the courts are currently too flexible is a matter of opinion, and unless you get nominated personally to the SCOTUS, an inconsequential one.