Sheldon Farough’s review published on Letterboxd :
I don't actually know how to feel about this movie.
There are a lot of things this movie did right. The darker tone worked really well for this type of story. The soundtrack was incredible and really punctuated the mood well. It reached above normal comic book movies with the "Shane" references/parallels and the "Old Man and the Sea" parallels. It emotionally grabbed me during a few scenes and the whole movie I kept asking these questions that made me really intrigued about the future they were in.
HOWEVER. My biggest problem with this movie was that I was very unsatisfied with all of the answers they gave to those questions (I'm referring mainly to the disappearance of mutants, and Wolverine's decreased healing). The answers they gave were so weak that it made me think harder about those issues and how A) it doesn't make sense when compared with other movies in the franchise and B) it actually presents a lot of internal contradictions. They made a big deal of the X-men being famous and getting their own comic books in the world, but nothing else in this movie would indicate that the X-men were famous other than a few plot important characters recognizing Wolverine.
Also I just want to talk about the darker tone. The story definitely facilitates a more adult and grim tone. So the R rating is okay. Except then they do a ton of gore effects so that it stops feeling like a serious movie and more like a sleazy horror or something. Also the more adult tone is contrasted so hard by villains who act and give speeches like very cartoonish villains. The big evil scientist guy and his pet weapon felt really out of place to me in a movie about growing old and protecting the next generation.
I don't know. I won't pretend this movie isn't good, but there were just certain elements that really didn't work for me. Also by the end, I was really wishing that I just watched "Shane" instead.