Classic horror formula brought back to haunt our modern times
I do feel this movie has a potential to one day become a classic of it's own. A good horror movie takes the things that plague the everyday lives of it's contemporary audience and exposes their dark side, but without spelling things out. Resulting in the audience feeling very uneasy, but not knowing exactly why. All classic horror movies pull that off and this one does an equally good job targeting a modern audience with modern issues.
Like with all horror movies that apply this formula (and all the good ones ALWAYS do) this movie therefore relies on building things up in the first act and having the audience relate to the characters and their relatable everyday issues and interpersonal conflicts. Which might seem dull (especially for today's audience with its notoriously short attention span) but it's an absolutely crucial and necessary build up for the 3rd act in which the bleep will finally hit the fan.
So while the everyday problems of an average modern family might seem boring to sit through and might seem like they have nothing to do with the scary monster that will figuratively and/or literally, but inevitably show up at the end, it in reality has EVERYTHING to do with it and actually any monster is merely the personification of the dark aspects of the issues that are addressed in the first act.
Also, like so many horror movies nowadays, this movie includes some references to the occult. But unlike in many other horror movies, these occult aspects are not in any way glorified, yet are portrayed fairly accurately, though of course taken with a slight artistic license. Which I think is what you would want. I mean after all and assuming black magic is real, you wouldn't want your audience accidentally summoning the dark forces after casually reciting some dialogue from the latest haunted house movie :-)