Well for a film called Dark Phoenix there wasn't a whole lot of Phoenix in it, Dark or otherwise.
Even if Disney hadn't bought Fox, I think this would have killed off the mainline X-Men films, just a mostly nothing film. I can't believe they had the same joker do this again. It feels like a completed Beta test for The Last Stand. The first half of the film is a nearly 1:1 repeat of Last Stand, but with a bit more cosmic stuff added and the crowded cure plot removed.
Open with flashback to Jean as a child, Phoenix appears in the present day, Jean is examined and off the charts, Xavier reveals he put mental blocks in her that she's broken, Jean flees to her childhood home, kills one of the team, then goes to Magneto, funeral for the dead team member, Storm does nothing.
Which film am I talking about?
It diverges from there, but I can't say it's much of an improvement. The villains are totally nothing and as far as being "Dark Phoenix", Jean barely even becomes Phoenix, never mind Dark. Other than killing Mystique, which is basically an accident (at least she deliberately killed Xavier in Last Stand), the closest she gets to being evil is...being mildly unpleasant briefly? I don't know why they marketed it as a Dark Phoenix Saga adaptation at all, at most it adapts some of the Phoenix Saga. It all feels tiny in scale and once again, ashamed of its comic roots, in spite of the additions from the original story like the space shuttle and actually having the Phoenix Force.
The score was good, I'll give it that, and the final action scene was well made. But it hits all the bad notes of Fox X-Men on the way out. Roll on MCU X-Men, needs a fresh set of eyes.