This raises an interesting question. Presumably you are referring to search results on a browser where JS/Ecmascript is disabled.

Another interesting place where Ecmascript comes into play is the pages that have been scraped. One difference between search engines is how they handle SPAs, and 100% Ecmascript rendered pages from frameworks like React.

I wonder if they execute JS in order to build good search results from pages that are React style SPAs.