Why are people so angry about... Maisie being a clone? For as poor of a movie I think Fallen Kingdom is a human being cloned isn't even an issue at all. Did people just think that cloning technology would only ever be used on prehistoric animals?

A lot of things that people are so angry about aren't even inherently bad, especially considering that the movie is clearly showing them all in a bad light. 

It isn't even the first time humans were cloned in the JP franchise for crying out loud, where were all the people claiming that "The franchise is being raped!" when Dinosaur Battles came out?