Don't confuse the revolutionaries with the Founding Lawyers. Patrick Henry and many others despised the Constitutional Convention and its results.
An oppressive government isn't a big deal if you are the oppressor. The Founding Lawyers were designing their future jobs.
The Federalists bought out and closed down newspapers that printed alternative views. The CC was held in strict secrecy. Madison's notes weren't made available to the public for decades. Hamilton and Madison concealed their authorship of the Federalist papers (which were a bait and switch)...and on and on and on.
Just look at the structure of the original government.
The President? Not chosen by "the people" but appointed by the electoral college which in turn was chosen by state legislature.
Supreme court justices? Not chosen by the people
The Senate? Not chosen by the people.
And who judges the Senators, President and SCOTUS ? Certainly not the people. The try and judge themselves.
Only the House was chosen directly by the people. You'll notice the Senate has significantly more power than the House. Gee I wonder why that is.
Oh, and the entire nature of judicial branch is left to Congress. That's some check and balance. They didn't even bother to specify the number of Supreme Court Justices. Do you really think that was a mistake? Furthermore, what interest do any of the three branches have in limiting Federal Power ABSOLUTELY NONE!!!
The Constitution was created by the elite to secure power over a rowdy illiterate mob. The system was specifically designed to preserve government power even against the wishes of the people.
Either the Constitution is powerless to prevent the kind of government we have today or it was deliberately designed to create a nearly unlimited government.
Which is it?
Our situation today is quite distinct from theirs.
We can do better.
The problem is that when present-day "experts" propose a new constitution, it reads like this one. Hillary Clinton often cites these articles (sometimes word for word) as if they were already part of the U. S. Constitution (see Articles 40-46, 52, 61, 67, and 69).