It's a reddit post[OP], that links to an article[1], that links to a specific comment in a reddit post[2] which is a reply to the actual comment[3] that contains the link[4] to a specific section of a YouTube video, which contains the actual confirmation.
After sifting through all that, they didn't give a reason, which is pretty lame, but alludes to the fact that it's helpful for them and not for you. Presumably this is step one in storing old videos on glacier-like storage so it costs them less (and inevitably will let them play you more ads while they retrieve it)
[1] https://piunikaweb.com/2022/11/10/youtube-sorting-option-for...
[2] https://www.reddit.com/r/youtube/comments/tx0uln/question_ha...
[3] https://www.reddit.com/r/youtube/comments/tx0uln/question_ha...