I think they just modify the status bar manually on hover. If you right-click a search result URL and copy it to the clipboard, it's the super long redirect URL, even as the browser status bar shows the URL you will be directed to.
If you are using a browser that prevents status bar fooling, you will be able to copy the original link and middle click to avoid tracking. If your browser allows it, then everything will include tracking.
https://developer.mozilla.org/en-US/docs/Web/API/Window/stat...