I consider all the 1 star reviews quite encouraging, as they are likely people who saw the cast and didn't see the genre (typical gramma & grampa going to the horror show, thinkin' it's a comedy).
Yet every single person has said that this movie made them think, and "stuck with them for days." ~That's what a good movie does, you see.
...and they are just proving the point of this masterpiece; that humans are a bunch of ding-a-lings, who find is easier to go along with the crowd, then actually live a life of authenticity (see the recent US election).
You likely know if this is your kind of movie or not, you don't need me to tell you to go see it.