The only thing in your whole post that I disagree with is the bolded. There is nothing "vague" about Superdad's hypocrisy.
Superman puts the world first. First and always. Christ, even Superman Returns got that part right. Maybe Superdad was helping people far from the League's fight with Darkseid. We're not told either way so it's entirely possible. But if true, then that still means he was ignoring the source of the problem so he could deal with the symptoms. It means that he was dealing with some parademons, saving perhaps a few dozen lives at a time, when he could have been taking on Darkseid, removing the cause of the threat, and saving billions.
Well, I know where he
wasn't. He
wasn't fighting the Crime Syndacite. He
wasn't fighting Brainiac. He
wasn't stopping Superdoom. He
wasn't helping Superman hunt down Vandal Savage. He
wasn't saving Perry White from a bullet. He
might have been ignoring the real threats, letting people die, and dealing with secondary problems caused by these Events. Im sure he saved some lives from the natural disasters Ultraman created when he moved the moon. But Superdad
wasn't there trying to stop him. He
wasn't acting like Superman.
The fact that many of these stories happened before L&C saw print only means that DC, its editorial staff, management, and Jurgens could not come up with a better excuse for Superdad being MIA from these Events than "He's keepin' it on the DL"
And these people are supposed to be professionals?