What if I told you one key did all this? One single keypress can bypass the greatest of walls, would you believe me? On desktop browsers.
To follow up: I had initially assumed that it didn't work on mobile because the browsers normalized the URL, however this isn't the case. The redirection happens on the server side. So, if you want this to work on mobile browsers, use the "Request Desktop Site" feature.
https://www.youtube.com/watch?v=DuB8VUICGqc // will occasionally show ads
https://www.youtube.com./watch?v=DuB8VUICGqc // will not show ads
It's a commonly forgotten edge case, websites forget to normalize the hostname, the content is still served, but there's no hostname match on the browser so no cookies and broken CORS - and lots of bigger sites use a different domain to serve ads/media with a whitelist that doesn't contain the extra dot
This works for many news websites as well serving paywalls, e.g.