I think the Supremes decided this really wasn't a state vs. state case. This was an outside state noting that what happened within another state was unconstitutional.
Personally I believe every citizen of the US should have standing to bring a case against every state that ran its elections unconstitutionally, but unfortunately it appears that you only have standing if someone has caused you to lose money. Truly sad.
SCOTUS is saying that the constitution declares the states are going to run their elections. And because the states have run the process through their courts, and election processes—and deemed them to be proper—then other states and the Supreme Court are not “harmed” by them.
Unless everyone here wants to change the electoral college....
I didn’t think so.
If not all the citizens of the U.S. at least the citizens of the State that violated its own laws.