> Just because a business no longer exists, the address still exists.

The address Świętego Mikołaja 18 is here: osm.org/node/4219750183

> The name of the business is usually listed under old_name

Not in Wrocław. We don't use [old_name] where there is no new name [name]. If there is a tag [old_name], there should also be [name]. The name is still visible on the spot. "Mango Mama" [name] is the name of the closed restaurant [disused:amenity=restaurant].

> they are data garbage

No. The restaurant is temporarily closed, and when it reopens, I'll remove the prefix "disused:". After you deletion, I wouldn't be able to do that.

You can write here which of the 21 tags were incorrect and we can discuss it. Because it looks like you're using some kind of validator that brought you here, and we don't map on OSM to satisfy some tool.