Near as I can tell, McConnell and Grassley made those decisions because they were — by the rules — in positions where they had the ability to make those decisions. And, if other folks in the Senate had taken issue with that, why, then, they, in turn, had the right, under the rules, to vote to change that up; but, well, they promptly didn’t, is all.
And, sure, you can chalk that up to “procedural machinations” instead of just saying “entirely legal maneuvers”, but the point is that (a) I don’t see you arguing that any rules of the Senate were actually broken; and (b) weren’t those rules the result of Decisions About Critical Matters Of Governance By Elected Officials, like you were just saying?
Oh, no rules or laws were broken, and McConnell and Grassley were perfectly within their rights to subvert democratic norms and Senate procedure that were the accepted standard for almost 150 years. Which is exactly the the point; Victor Emmanuel III ensconced Benito Mussolini as Prime Minister of Italy and Adolf Hitler was appointed Chancellor of Germany by Paul von Hindenburg in procedurally legal, if ethically dubious manner…and no rational person today would argue that these were wise decisions that lead to equitable outcomes. Democracy is more than just about the Rule of Law; it is literally about compromise and inclusion, to an end of reducing the propensity for insurrection. The GOP, on the other hand, is now cleanly on record of at least being deliberately obtuse about deliberate attempts of subjugation and violent overthrow of legitimate electoral processes, and they’re getting more brazen about their adoption of autocracy by the day.
The sort of insular rejection of democracy and oppositional defiance has its roots in the Southern Strategy (which itself was an exploit of Jim Crow-ism), but it’s modern incarnation arguably started with Lee Atwater and found its enduring voice in Newt Gingrich, who like a bad fungal infection will just not go away no matter how bad he stinks up the joint. Still, Trump was a revelation in just how bare-assed one could be about in being a feckless autocrat as long as you didn’t try to apologize for it, and DeSantis et al are right behind his clown car taking notes on what works. If Trump were just smart enough to listen to the actually intelligent people in his orbit like Steve Bannon, he wouldn’t have lost the election and there wouldn’t be another. Fortunately (at least for now) Trump thinks he’s the smartest guy in the room which isn’t even true when he’s taking a 3 am dump in the crapper. We will probably not be so lucky the next time around.
But you could likewise name times when no rules or laws were broken, and people acted perfectly within their rights, to change things for the better in procedurally legal ways: discarding what had been — which isn’t to say had been good, because, again, sometimes change is for the better — in ways that, as you say, rational people today would argue were good and wise and so on.
Try as I might, I can’t tease a semantically meaningful point out of your post. Regardless, McConnell and Grassley weren’t on some campaign of benevolent improvement of the democratic process; they engaged in a bare-assed effort to subvert democratic norms and deny the opportunity for a nominee to even receive a hearing because they feared the consequences of equitable procedure, and then when the situation was reversed with a nominee who fit their partisan notions of an ideal candidate, farted all of their previous rationale into the elevator without even a sheepish grin. And this is the modern GOP as a whole; a party dedicated to a groupthink that is more important than adherence to any ideals of democracy or representation, who are actually so fearful that their positions are not tractable to the public that they have made great efforts to undermine the electoral process and deny the franchise to those they don’t believe they can appeal to.
Ronald Reagan, no middle-of-the-road Republican (at least, in his contemporary setting) understood that the legitimacy of his governance came from both popular consensus and a willingness to come to terms with those he disagreed with, and as such, built bridges with liberal Democrats to achieve many of the things he thought were most important, and find equitable compromise on those where the majority did not share his views. He was not beyond using the rhetoric of fear and uncertainty to influence public opinion, but also to moderate his own views where he was not in the clear majority, often coming around to agreement. Of course, he also lied and manipulated the law where he thought he was in the right regardless of public opinion and Congressional mandate, and then used his influence to avoid the consequences…which worked out just fine for him and everyone who went along with him, and threw the oppositional Bob McFarlane under the bus. Guess what lessons the modern Republican party drew from the Iran-Contra affair?