I don't believe it's all black or white and actually hate your comment. Suspension of disbelief is a spectrum and every fan has a place where they draw that line. I don't think it's fair to tell someone where they should draw the line.

For some people, that line is drawn at the Irish Whip. For others, it's the snake puppet having a mind of its own or a penis suplexing another adult. For others, it's at various places in between. Just because you accept one thing doesn't mean you have to accept everything else. I can accept the undead wizard because he doesn't use magic during fights and even without the magic, I believe that he'd be able to whoop some ass.