Separate source of truth from derived data. Separate possibly valid user intent from validated state. Use contexts to organize the data dependency graph of your application. Ensure all your widgets use a consistent value type in and out, don't let events contaminate it. Use something like cursors or optics to simplify mutations and derive setters automatically.
I've never had an easier time building very complex UI functionality than with React. But it requires you to actively start reasoning about change in your code (what doesn't change), and this is something most people are not used to.
Personally I think React compiler is folly for this reason: they are taking the most interesting part of React, the part that lets you write apps that are incremental from top to bottom, and telling you it's too complicated for you to think about. Nonsense.
The issue is just that React makes pros feel like idiots unless they eat some humble pie and grok the principles and the reasons behind it. Which is that React is what you get when you try to come up with a UI architecture that can make entire classes of problems go away.
Without a VDOM, one way data flow, and diffing, your UI won't just be slow, it'll be full of secret O(n^2) cascades, random ifs to stop infinite cycles, random "let's update this state early so other code can immediately use it" ordering issues, and so on.
