Thats whole point, only doing this for important you tube videos where not sure author will keep their site up in 5-10 years.
But have noticed over years, some videos I have kept, 5-10 years later, try to play and Apple says not supported or play with.. stuck.
There is no guarantee that if you keep any electronic media format that long that it will still be supported, or that players will still be available, or that you will still have a device capable of running the player if you still have one or even if it is in a playable format and you have a running player app, after ten years there is a substantial
probability that unless you have replayed, reformatted, and resaved the files regularly (say every couple of years), the data may have begun to decay and may not be anythng you would enjoy watching. After all, 4K flat screens are so boring after you have become accustomed to 46K VR displays!
