Congress and the Senate are meant to be reflections of the states individually, not the nation.

The House of Representatives is supposed to be representative of the people; that's why a member represents a district, not a state.

The Senate was originally elected by state legislatures, but no longer is. And the purpose of the Senate was to preserve slavery, by ensuring that states which were economically dependent on slavery would wield power disproportionate to their (free) populations. And even the 3/5 "compromise" was an attempt to inflate the qualifying populations of Southern states for the House of Representatives.

The pre-Civil-War history of the US Congress is literally the history of the Southern bloc using their overrepresentation to preserve slavery at any cost. That is why it was set up as it was, and the eventual cost was a four-year civil war and hundreds of thousands dead. Oh, and the perpetuation, for decades, of a brutal system of chattel slavery whose toll in terms of death and misery is likely incalculable.

Same thing for so many other aspects of the "originalist" approach. Electoral College? There to ensure slaveholding states get represented out of proportion to their population in presidential elections. States' rights? That's a state's right to enforce slavery, backed up by fugitive slave laws and eventually by the Dred Scott decision essentially stripping the rights of northern states to prohibit slavery within their borders (since that would be an unconstitutional taking of a southerner's property, should he choose to visit the north with his slaves).

And today, what do we see? Much the same bloc of states using their overrepresentation to impose their will on the majority. This has never been good, and it has never been stable. Let's fix it.