I mean, there is nothing special about this at all.

Such premise has been done before, watch The Happening or Pontypool. At first it borrows from The Happening, then from the Night of the Living Dead, Dawn of the Dead, then The Road (or Cargo, whatever), then A Quite Place. I predicted almost every major scene and the ending of most of the plot lines they had. It was super predictable and never really interesting. I did not expect any answers and I'm ok with the movie not explaining anything, but this just wasn't particularly interesting for me.

It's a movie you can expect from Netflix, good production, marketing and promo baiting you into checking it out, but the movie itself turns out to be pretty generic and not particularly interesting.

P.S. In my opinion, Sandra Bullock wasn't the best choice for the role either. Imagine this with Essie Davis from The Babadook, damn this would've been much more intense.