That's a fundamental misconception of the Constitution, and here I'd offer you the same response you're giving others - the Court disagrees with you. They still require that any law implemented by the federal government rests on specific powers granted by the Constitution. In fact most of the 'work' they do involves finding ways to rationalize federal power in terms of the enumerated powers. If your view held sway, they wouldn't bother.
Regardless of what you believe the work of SCOTUS is, they do it as prescribed. What we have is what the Constitution prescribes.
I think that it is useful to consider that the Constitution is a product of diplomatic compromise. Opposing views were resolved. Mostly the opposing perspectives stemmed from states rights vs a strong union. Not between strong vs weak government.
Like we expect from diplomacy both sides were satisfied. The federalist thought that the general clauses adequately described a strong union. The states rights people thought that the specific limitations did not usurp the authority of the separate colonies. The autocratic founders really didn't worry much about we, the people, but understood that their vision ultimately rested at our pleasure as we didn't have a traditional aristocracy in place.
The bottom line, which is the strength of the document, is that it can be interpreted multiple ways. But, as time has gone on, the strong union has become our greatest strength, reinforcing that interpretation.
You don't have to agree with the conclusions of history but they will remain.