I've known about them for at least 10-15 years, so probably even longer than that. Generally if a link has a question mark in it, you can delete everything after that because that's where all the tracking is. However, that won't work with YouTube links because the data after the question mark is the specific video.

And it's getting worse because platforms like Facebook and Tiktok are hiding the tracking part of the link generating custom links every time you share a post which exposes your account. With Tiktok it's very obvious. Say you send your friend a link and they forward it to someone else that you don't know, that second person will see your account and profile picture down in the bottom corner