The "performance angle" isn't really an angle. It gets bandied around by junior devs new to React, but it's not the primary selling point of React - in fact, it's not a selling point at all. Don't believe me? Just go to http://react.dev and look - no where on the site does it say that React is a hyper-performant library. It's not! If you need blazing performance, you're best off using something much more minimal, or even vanilla JS.

When people say that React is fast, what they mean is that React can dom-diff faster than a naive O(n) approach. It means that updating a component with a thousand nested divs won't crash out your browser, like it might if you were to write the code by hand. It doesn't mean it's an objectively high-performing framework.

What React is good at is forcing you to write code in a clear, comprehensible way. Having every engineer on your team obey F(props) = state is a strict improvement over virtually any other paradigm. (Yes, you can still make a tangle of components if you try hard enough, but the complexity of the tangle is capped significantly lower than the complexity of a tangle of JS without any framework attached.)