This question seems misaligned(?). The idea is that it's easier to work with and harder to fail when complexity is hidden beyond a good interface. The complexity of a good UI framework's interface is low by definition. React exposes way too many moving parts and has way too many breakable rules to be called good. All UI frameworks may be as complex as they want, the interface is what matters for an end-developer.

Svelte's interface is basically "I will re-execute top-level statements starting with $:".

Vue's interface is "I bound your data to html, feel free to update it, but beware of []-nuances".

React's interface is "You have to use state and effect wrappers, but don't effect in non-effect blocks (and read what an effect is!), also always make copies of everything, and we can run your code twice, and if you if (), then make sure you don't if () in an inappropriate place, anyway, imagine you're in a pure functional language, but you aren't really, so do that by hand and don't mess it up, we warned you".