A really simple script that just redirects YouTube shorts URLs to the regular YouTube player.

redirect_yt_shorts.js

// ==UserScript==
// @name         YouTube Shorts Redirect
// @namespace    http://tampermonkey.net/
// @version      1.0.0
// @description  Redirects YouTube shorts links to the regular youtube video player.
// @author       Chev
// @match        *://*.youtube.com/shorts/*
// @icon         data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==
// @grant        none
// @run-at       document-start
// ==/UserScript==

(function() {
    'use strict';

    location.replace(location.href.replace("shorts/", "watch?v="));
})();