The file is yours, and so is the expiry date
Begin with what is actually true here: the recording is made on your presentation platform, stored wherever you put it, and served by whatever sharing rules you set on that file. My Joyfullday holds the link you paste, not the video. That means nothing on our side expires automatically, and nothing on our side can stop a link being forwarded.
So the length a replay stays available is a decision you make twice โ once about the file, once about the page. The file may be moved, overwritten or made private without warning to anyone holding the address. A link that stops working silently, on a page people still visit, is worse than a replay you retired deliberately.