Vacancies in all offices for the State at large, or for districts larger than a county, shall be filled by appointment of the Governor;

The Senate has always been treated as an "office for the State at large".

I am not sure how to say this without sounding like an asshole so please take this kindly: Are you aware that the Constitution of a State can only apply to state level government and has no application to the federal government?

Yes, it can be confusing because Senators in Congress are referred to as Senators "at large" because they do not represent a specific part of the state. What you quoted is not specific to senators but offices at the State level that are "at large". That would include offices that serve the whole state, like the Attorney General.

I really don't get why so many supposed Dems are arguing to lose.

I'm not sure who you are referring to. I'm not really following what the Democrats are saying about this. Therefore I cannot reply. If you want to share an example, I can try.

Is it better to win this argument than the country?

Maybe you aren't asking me this but I don't follow.

What's your motivation here?

The desire for people to understand how their government works. So that they will be able to clock when people are lying to them and ask themselves what there is to gain from these lies.

And for some reason you're taking their side, even when it's weaker.

I'm trying really, really hard not to respond to these comments because it's a distraction. My whole point has been that it benefits any government for people to fight among themselves rather than turn to collective action. But I am weak so here it goes:

You keep bringing up sides. What sides? Americans have been tricked into treating politics like team sports. How's that working for you? Has anything improved or moved in any way in the last 70 years? Are people more free? Have civil rights improved? Or is it convenient to present complex situations as two parties who constantly blame each other for failure to act while maintaining their positions of power? It's literally good cop-bad cop. How do people fall for that?

All I have tried to do was explain what the law says. I even included what path exists right now to make the seat vacant. What sides are there? Is it "the law does not allow for this" vs "he should do it anyways"? Do you understand those aren't opposites? "The law does not allow for this" does not assign a moral or ethical position. It is the beginning of a discussion, not the end of it.

If I was american I'd be asking myself why the focus is on this one governor and instead of all the senators. No one is questioning if the Senate can expel him. Have I missed why no one has done this? Maybe if they frown enough they can ride this situation to success in the next election and no one will question why they do anything. But sure, let's not try and under how things work.