Vue doesn't require nodejs to follow along with the examples
Vue doesn't prescribe to me how I should write my markup (beyond Angular-style attributes) or force me to violate separation-of-concerns.
Vue doesn't require it's stuff to be stored in $ROOT/app/assets/javascript/components, when all the rest of my code lives in $ROOT/app/whatever
Vue doesn't (or didn't) prescribe all these stupid little companion addons to do things I learned how to do (and do better) years ago
Vue doesn't give me a shitty markup language (JSX -- class vs className? Fuck off!) or even worse alternatives (its super verbose JS-DOM alternative) if I don't want (or can't) use it
Vue doesn't have nearly as large of an obnoxious, inexperienced, harebrained, and cloud-huffing crowd that will argue with me when I express distaste in it
Personal insults aren't cool.
If you want to use React with Rails, use Rails in API mode and keep the front-end separate. I'm not sure how rewriting in Vue is going to solve any of your problems at all.
"The browser loads scripts, why can't that be enough?"
Not sure what you mean by this. Whatever you use, the browser will be loading scripts.