[percyhanna]

By a custom renderer, are you referring to replacing the rendering process (e.g. ReactDOM) rather than replacing JSX?

It's not clear to me how this would be better than swapping out the @jsx pragma. For rendering content to the Canvas, we have no need for all the overhead and complexity of React elements/components. There is no need or benefit in using the `React.createElement` (or its newer counterparts) to create React elements. But in theory, you're right that CanvaSX could have used React elements and rendered those instead of replacing the JSX pragma.