The web environment was never intentionally designed to be what it has become (a system for drawing fully featured user interfaces and even games) and so isn't really equipped for it, you could argue it's missing a lot of widget primitives, the view-updates-as-string-manipulation is archaic to put it kindly and the whole thing is untyped and shackled to a weak language without so much as a proper this keyword.

This environment is simultaneously so restrictive (in that you can't really introduce new languages except by having them transpile to JavaScript) and so bad that people end up trying to tie it into something more cohesive (React's virtual DOM, Typescript) and then only partly succeeding (React's dependence on setState and things often being much easier to do with document.getElementById than in the React way, Typescript's inability to handle libraries intended for the web), leading other people to try do it better.