It's a very stupid argument to pretend that your opposing party thinks the sun will not rise if x or y happens.I have NEVER heard anyone use this argument, although I hear the reverse plenty from people who are avoiding making serious points by dancing around with comments like this. So let's get this clear:
The Aztecs occasionally missed a sacrifice, and the sun did rise.
The Roman Empire withered and died, and the sun did rise.
Hitler killed 11 million or so in concentration camps, and the sun did rise.
Stalin worked another 30 million to death, and the sun did rise.
17,000+ abortions in NZ last year, and the sun did rise.
Children killed in mass shootings, and the sun did rise.
Friends and family diagnosed with cancer, and the sun did rise.
A piece of legislation passed, and the sun did rise.
No-one really expected otherwise. Seriously.
The actual argument being made is "I don't foresee any negative consequences in action x", or perhaps "whatever the consequences are, I don't care as much as I want x". That's an OK argument to make, because it sets out a position that then can be discussed. The former approach just seeks to denigrate the other person by combining mockery with exaggeration. Let's try and lift the game a little.