@dwenius This is perhaps a *little* overstated. I'm a retired software architect here, so believe me there are many good and unharmful uses for query strings, so let's not go overboard. But you're quite right that in many cases they are not absolutely necessary for a given site or page.
To test what is needed and what is not, I will often paste a URL into the Address bar of the browser, try removing a chunk of a suspicious query string, hit Enter and see if it takes me where I want to be.