The same principles apply around the world. The U.S. recently invaded a sovereign nation and abducted its democratically elected leader because that leader was ostensibly involved in shipping cocaine to the U.S.
The only election for the president that matters is the electoral college. What the citizens are voting on is a referendum to choose the electors (and in some states it is not binding). You might try to argue that the referendum was rigged somehow, but rigging the electoral college voting is even less plausible.
Trump was talking about how Elon campaigned for him for a month in Pennsylvania and said he knows all about the voting counting machines in Pennsylvania.
Even if Musk did something in Pennsylvania, Trump still would have won the electoral college vote.
I think the good faith argument is that Musk confirmed they were secure so that the election wasn't stolen from Trump. But frankly Musk is too much of an idiot to steal an election or make sure it is secure so I don't know how to take it...
So what? The only reason the U.S. did this is because it can. What will the UK do when 4chan tells its online regulator to go suck a d***, send in James Bond?