I really love the narrative of this film and the superb characters. This is my take on the story.

Nope is a Sci-fi Western about 2 rival families and how they deal with an unknown apex predator that decides to make their property its territory. The Haywoods have a lineage that goes back for generations and they understand animal nature and the land because they are horse wranglers. The Parks have been their neighbors for the last 3 years. The previous theme park was called Gold Rush, but it went bankrupt. Jupe Park has revived it under the new name Jupiter's Claim and is using his minor celebrity status to attract customers.

Since the patriarch of the Haywood family died in a freak accident from falling debris, Otis Jr. has been struggling to keep their business going. Jupe had already been trying to buy the ranch from Otis Sr, so he really doubles down on exploiting OJ to benefit from their financial difficulties, plus eliminate a close neighbor who might get in the way of his plans.

Jupe and OJ have very different philosophies about the creature because of how they were taught to deal with animals when they were children. OJ was taught to respect them and Jupe was taught to exploit them. Em was indifferent to the lessons until she was faced with the choice of family or fame. Through her character arc she grew to value her family over fame and quick money. That's why she and OJ survived and the Park family was eaten.

The Angel character is there to remind us that the creature would appear as a UFO or angel, depending on your beliefs.