Just out of curiosity, is there anything wrong with deleting an old video for whatever reason, or deleting it and reposting it afterwards?
Has anyone done this?
I'd say the "Best" or "only" way I'd delete a video and re-post it is if the video was never performing in the first place, and in hindsight, the editing and flow could have been better. So if you can improve the original video somehow, in some cases I think you could get away with it, and it's something I've been considering with some of my original older content.
That said, if you don't plan to change anything about it, I'd argue what you plan to achieve? How will the results be any different to the first time posting?
What I'd also do, before deleting is gather all the relevant data such as overall audience retention percentage, and thumbnail impressions and CTR, and once re-uploading, see if there's actually any notable change. I'd do something like that on an experimental channel just to see if year of release has any impact on overall data.
Another question, why can't you simply remake the video? Do a slightly different version with a new filming and editing style, change up the dialogue, and point out that it's an updated take on a very old video, and that might make you less likely to be called out for "recycling old content for views"