I don't disagree with this — I was referring to the how does React do it part specifically. Although I'd also note that in practice people tend to use a subset

I don't disagree with this — I was referring to the how does React do it part specifically. Although I'd also note that in practice people tend to use a subset of JS in their work, and often prototypes aren't directly used. (I understand they power everything under the hood but I'm talking about something product engineer has to think about.)