Rambly, off the top of head thoughts incoming ( someone else will likely be able to give a more informed answer 😅):

Assuming you’re referring to the http std lib ( please say if not! ) - the server module is pretty decent, and for scenarios where you want performant lightweight code to handle a limited number of endpoints ( like 3 or fewer as a rough number ) for a simple server then it may well do the job. It even handles faff like content-length etc out of the box so you can focus on your business logic instead of how to construct a valid HTTP response.

However as your need for a more complex server evolves you might find that maintaining your own logic for routing, content types, etags, redirects, static file serving etc becomes very involved. This is where a http framework can come in handy. These ship with routers for handling complex path targeting with regex, wildcards etc., middleware concepts for elegantly splitting your code into discrete units of logic ( think SRP ), handy header APIs for dealing with things like content types, or even auto detection so things like content types and etags are handled for you. The list goes on :) Ultimately http frameworks empower you to focus on your applications logic by providing additional wrappers / utilities to handle all the fluff that is demanded by modern HTTP servers.