> But there is a ton of collateral, videos, etc. that companies produce that get stale, musty, or just plain wrong
That 2017 product roadmap slide saying "we'll deliver X version N+1 by 2020" gets a bit embarrassing when 2023 rolls around and it is still nowhere to be seen. Maybe the real answer is "X wasn't making enough money so the new version was cancelled", but you don't want to publicly announce that (what will the press make of it?), you just hope everyone forgets you ever promised it. You can't get rid of copies of the slide deck your sales people emailed to customers, or you presented at a conference, or in the Internet Archive Wayback Machine – but at least you can nuke it off your own website. Reduces the odds of being publicly embarrassed by the whole thing.
Or your 2011 presentation about cloud computing didn't mention containers. I'm not sure it's embarrassing any more than a zillion other forward looking crystal ball glimpses is embarrassing. But there's no real reason to keep on your site unless your intent is to provide a view into technology's twisty path or the various false starts every company makes with its products.
That 2017 product roadmap slide saying "we'll deliver X version N+1 by 2020" gets a bit embarrassing when 2023 rolls around and it is still nowhere to be seen. Maybe the real answer is "X wasn't making enough money so the new version was cancelled", but you don't want to publicly announce that (what will the press make of it?), you just hope everyone forgets you ever promised it. You can't get rid of copies of the slide deck your sales people emailed to customers, or you presented at a conference, or in the Internet Archive Wayback Machine – but at least you can nuke it off your own website. Reduces the odds of being publicly embarrassed by the whole thing.