Those amendments were substantial changes in how the Republic has functioned.16 gave control of the money and production progressively to the central government. 17 changed the Sovereign States into Provinces with no representation in the Central Government. 19 slowly but inexorably changed the focus of the Republic from liberty to security and making everyone be nice.
You give terribly short shrift to an even more fundamental spiritual shift. There is no secular way, not even the most supposedly originalist constitutionalism, to keep men from doing dirt. None at all. Let’s not confuse form with essential substance.
In fact the current form is the most propitious for a visionary figure like Donald Trump. We only need one Trump to get it started, not 50 Trumps.
I.e. doing dirt 50 different ways isn’t liberty in anything more than the most abstruse sense.
The same things abused by settling for “niceness,” as you put it, can also be used to bear forth holiness.
God knows what America needs, for the purposes to which He wishes to put it, even more than we do.