I think independent media has the biggest potential of becoming “lost media”. With potential no other copies of this media accessible online, I find it increasingly important to have this backed up.
You’ll always be able to find a copy of Forrest Gump online, but go through your liked videos on YT and see how many are lost forever.
Removing inactive accounts is one thing, but they’re also cracking down on ad blocking. Could be a first sign that they’re going to be working on stopping YT downloads