You hit on the problem without seeming to realize it. The Senate didn't delay the heck out of anything. McDonnell flat out refused to do anything about Garland's nomination. He declared the nomination "null and void" based on no precedence, case law, and certainly not any interpretation of the Constitution. The Senate majority leader should not be able to shut down the Senate and prevent it from performing its Constitutionally mandated tasks. If the Senate didn't want to confirm Garland they should have held all the appropriate hearings and held an approval vote. If it's the Senate's will that Garland not be approved that's fine. It was singularly McConnell's will that Garland not be approved so he just never allowed hearings. No matter your political leanings that should be seen as abhorrent if you profess to want law and order.

Wow, being a bit insulting there. I am stating how it works. The Senate Majority leader can do it. That's how it works. Supposed to doesn't really matter when talking about what will happen.

Ultimately a legislator's job isn't to respect precedence or case law. It's to create new law (and presumably precedent).

I don't think your point is unfounded, I just think arguing for a legislator to behave like a judge takes away from that point (unless you have a good argument why they should, but I think including that argument would be good at that point).

Not sure what the calculus is. If it’s unfilled, Biden will fill it. If it’s filled, he’ll expand the court. Not sure if that also depends on a senate flip, but I have a hard time believing the senate doesn’t flip during a Biden win.

Note that Trump and McConnell are rushing to fill the Supreme Court, despite 4 years of leaving about half the government posts vacant.