Wouldn't it be the movie starts at present then it turns into a flashback for the majority of the movie then it goes back to the present for the wrap up?
Especially when they show a bunch of dead characters, and then you rewind and see them kissing their kids goodbye or petting a puppy and promising to take them to the park when they retire tomorrow. That's just emotional manipulation, and it makes me feel detached from all of those characters. "None of this backstory matters because they will all be irrelevant to the story soon."
Then they do that bullshit fakeout "haha, nobody was actually dead, they were pretending for some contrivance so we could make you think they would be dead. Eveybody is alive and the puppy does get to go to the park!" That's not a happy ending. Go fuck yourself, that's a happy ending. You, the filmmaker, fucking off and stubbing your toe, that would make me feel better about your attempt at forcing me to care.
This is the literal reason I could not watch the new lost in space series. The first episode was flashback hell and I never bothered to go further than that. If you need to keep flashing back to "the start of the story" maybe you should just fucking start there.
On the flip side, I recently watched Scorsesi's Casino for the first time which starts with Robert DeNiro's character getting blown up. Was a great movie still.