The deus ex is certainly prone to abuse, but I can see its use in situations where you’re focusing on a character’s reflection, helplessness, etc, or in a comedy that’s not taking itself seriously. (Or, in a superhero story where it’s pretty much a given.)
I generally avoid deus-ex’s, especially “just-in-the-nick-of-time” as the countdown reaches “one second remaining” types. My distaste grew while working on my potter fanfic ages ago because it kinda destroys realism in the odds. Sure, occasionally there’s a white knight that shows up, but not very often. Most very often, the victim perishes. And, developing a reputation to not write deus ex helps with the suspense to the reader, because they won’t know if character in distress will live or die
- DP