Well, last time I checked, you could use a lot of these out of the box, as long as you didn't mind dropping support for old Internet Explorer versions?
A lot of these, but not all (JSX for example). And then you have to worry about support - caniuse is great help, but it gets very tiring.
But to me the main benefit is something else. React & co. let you define the state and then rendering based on that. It is incredible what this means for code maintainability... Try it, it really is worth the effort.
I've since decided to boycott JavaScript as a developer, and to block it everywhere I could as a user. (And rendering should be decided by the user's browser.)
