It would be cool to have a feature like that, similar to how you could see previous years in Street View. Closed restaurants are preserved on Yelp, maybe there might be a way to extract that somehow and put it on OpenStreetMaps…
OpenStreetMap is for currently existing features (or currently existing remains, ruins can be mapped). So if for example sign remains, it can be mapped. But once fully gone: it is not mappable in OSM.
If it were up to me, I’d recommend keeping it with a flag that notes it as closed, rather than deleting it. (Just as you can mark a row in a database as deleted and not physically delete it). I know it’s not that simple. :)
I’ve seen cases on Google Maps where a previously bookmarked restaurant, after having closed, will completely disappear there. It used to be that bookmarks of closed places would still work for some time - you could still read the reviews and see the photos.
But now, I’m finding more and more of these bookmarks just pointing to a lat,lng point. True digital rot/loss. It’s really sad when that happens - that was one of the impetuses for creating this site.
As long as there are traces - it can be kept `disused:amenity=restaurant` rather than `amenity=restaurant` etc.
But once fully gone it should be removed - this way OSM data can be always verified/updated by visiting a given place, without being aware of now gone objects there. And keeps it objective - otherwise you would run into big discussion "where was this restaurant closed 20 years ago?"
Or "how this castle was structured in year 1450" where you often have multiple competing reconstructions.
