Advertising or data-mining supported services are not free. We are still paying in time or headspace or personal data, so it is perfectly valid to have a problem with the quality of service we receive in exchange for that payment.

That's fair, most of the videos have no or little personal value, if bit rot occurred I most likely wouldn't notice up to around a 20% change.

Average length of time of those videos is around 5 minutes, total size ~135 hours, or ~150-200GB.

I could store a personal mirror, of much larger size for almost nothing, disregarding legality of such, but the data is less important than the references in a large number of cases. I don't care about the content as much as the ideas the references help recall, in most cases.