TL;DR it's slow. Way too slow.
Semi spoilers ahead
Starting with the positives, the.dislog is organic and well thought out, the revelation at the end is cool. Well, kind of.
I appreciate that, at strong junctures in the movie, the pacing slows down so we, the audience, can let it sink in. The problem is, the pacing rarely picks up.
The actors do a great job. As they should, because we spend 95% of our time with them. The only time we get to spend away from watching the family is when we get to watch what they are watching on TV. The great big aliens are seen as rarely as bigfoot. And whenever they're seen, the camera is shaky, or out of focus, or we just have to make-do seeing their reflection in an old tv. Makes me wonder how they even utilized the entire budget.
I especially had an issue with the kid saying that "they only survive on a plant based diet because they realize it's a healthier alternative" trust me, you won't miss this subliminal messaging.
To add to the monotony, there's not many scenes away from the house and the house itself isn't very interesting. It's teased that the house is present in some ancient books, but that revelation is quickly forgotten.