"Hereditary was trying to setup a "normal" suburban environment"
I don't think that was the intention at all and am wondering what gave you that impression. That was one of the things that separates it from the herd IMO. 9 times out of 10, we would have gotten exactly what you're talking about- we would have probably met the grandmother and watched her passing, being made to feek sympathy for her and the rest of the family right off the bat- which seems cheap, easy and predictable. And to say there is NO tonal graduation is a bit misleading but again, that's not something I need in a horror movie.
"Rosemary's Baby" is the type of concept that sounds good on paper (anyone read the book?) but I'm sorry, I just find the film to be cheesy and I personally don't feel the sense of dread or unease that I associate w/ the most successful horror films I've seen. It's ok if we disagree- I still like you