> I'm not sure I'd ever expect a framework, React or anything else, to stop that behavior. If a child component signals to a parent that the state has changed then I would always expect that to cascade down the node tree. That could cause further updates. And more renders. That behavior is on me. If the framework decided not to cascade some updates that would be weird.

It's not that the properties shouldn't be updated it's that in React the whole subtree gets completely re-rendered, with a potentially big performance cost. Svelte just changes the relevant bit of the DOM, like a single class attribute or whatever, and leaves everything else be, this feature alone is what made me switch. In addition to baseline performance benefits certain things which are really awkward in React (e.g. animated transitions) become non-issues.

>Feeling like you have to stick with React is a state of mind - you can change that with enough effort.

I really appreciate your optimism about switching to a different framework/ etc. and I would have felt the same earlier in my career where I didn't have so many non work commitments, financial and otherwise. But to me now this reads as wishful thinking; switching track is difficult, especially when your existing skill set represents a large chunk of the demand in the marketplace. (And I say this having recently sucessfully made the switch from React to Svelte)