I see that oftentimes this stems from the lack of knowledge regarding how the system underneath (VDOM, DOM, JS VM, computer ) works. Case in point: why are (or

I see that oftentimes this stems from the lack of knowledge regarding how the system underneath (VDOM, DOM, JS VM, computer ) works. Case in point: why are (or were?) anonymous functions frowned upon in React props? Is it because of the penalty involved with creating a function on each render call? Of course not - my phone can do 19mln of those a second. It's because the VDOM sees a reference change, so it re-renders the component. Obviously if there's a performance penalty, it's because of the latter, but I heard the former before as an argument in a discussion.