I remember the concept of the virtual dom had to be explained very carefully so people understood why it led to more efficiency when rendering (e.g.) scrolling content.
Is there a technical trick that one takes that can beat a virtual dom use case? What is it?
Yes, it's an easy trick: just rerender the tiny parts of the DOM that actually need to change. Like Svelte does, only with run-time magic, instead of compile-time magic.