First of all, I'm not saying or implying that this reviewers opinion trumps all other reviewers opinions. I'm just saying that if a superhero movie doesn't have a lot of action in it and is a mostly talking heads borefest, that it is a deal breaker for me.
Secondly, saying that the "action is great" DOES NOT mean that there is a "lot of action" or "long action sequences" in the film. A film could have the best damn action scenes in the entire history of cinema, but all of those action scenes combined could add up to about 10 to 20 minutes out of a 2 hour movie (which was the case for the first X-MEN movie). That being said (and for the sake of fairness), this movie could have a lot of action in it, but not enough action scenes showing BP punching and kicking bad guys, which seems to be what that critic with the "negative" review seemed to be complaining about. Heck, Priest even said that that Dora Milaje got all of the best fight scenes in the film.