I think understanding when a movie is just for fun is part of a film critics job.
In Australia we used to have Margaret and David before they recently retired. They were really good film critics with tastes that covered a large spectrum of movies.
On the other hand, there's "Man Getting Hit By Football"[1]. One can find a film too simplistic to be appreciated even if one takes it as "just for fun".
As people whose work is very subjective, critics don't lend themselves to be read in an ad-hoc fashion, in my opinion. One should follow their reviews, compare them with the works one has also watched/read, and only then decide which critics are more appropriate for you.
In Australia we used to have Margaret and David before they recently retired. They were really good film critics with tastes that covered a large spectrum of movies.