Most web applications are not written in Java. NGINX also allows static assets to be served directly while side-stepping the application server. This is a boon for interpreted languages.
Maybe in Java-land it’s overused, but everywhere else it makes sense.
I'd also say that there is no such thing as a "general case"; I've launched and/or supported countless (must be hundreds?) of web projects and even the "simple" ones were each a bit of a snowflake.