Minor nit, because this is one of my weird special interests: this (being render-agnostic) isn’t necessarily a property of React’s virtual DOM. It’s a property of JSX being explicitly specified without semantics.
For instance, Solid also supports custom JSX renderer, but doesn’t use a VDOM to achieve that.
I find it helpful to think of JSX as analogous to a macro (in the lispy sense of the term), except that its syntax and implementation are decoupled. Most compiler tooling assumes the implementation maps to a function call, but even that isn’t strictly required (and again, Solid is a counter example).
For instance, Solid also supports custom JSX renderer, but doesn’t use a VDOM to achieve that.
I find it helpful to think of JSX as analogous to a macro (in the lispy sense of the term), except that its syntax and implementation are decoupled. Most compiler tooling assumes the implementation maps to a function call, but even that isn’t strictly required (and again, Solid is a counter example).