Using Lower Merion as my area of residence and examples here, there are dozens of former estates that are/aren’t named haphazardly. Many of these are named on old atlases of the area.
For example:
Gully Run Acres: A name added by me, as it appears on the mailbox. Built with the other items on Sandringham as a development rather than an estate
Skylands Mansion: A site once known as the Mary Drexel Home, now an immense estate
Hillcrest 1911: Named presumably for its name and build date, this and many others were added ~9 years ago by geonarb.
Knollbrook/Camelot 1917: Score another
The Maples: And another
This atlas, for example, has many, many names of estates, some/many of which exist today.
Don’t you mean addr:housename?
Never seen that tag before, in all honesty.
Assuming all of these need to be changed in that case?
I have some doubts about addr:housename being applicable for most of those examples.
Where I live “addr:housename” is only used when the name is part of official address. In rural regions there there are frequently no named streets. And even if they were named if it’s a single house next to a road in the middle of nowhere having the house number hardly helps locating the place. Instead postal service identifies such houses by their name+local municipality name. This seems to match with addr:housename description on wiki.
In all the examples above there seems to be proper street/house number.
Having a well known name doesn’t necessarily make it part of address. Also addresses are not set in stone, just because historically place was identified one way doesn’t mean that it’s still the official address.
Absolutely you can add name=* to a house that has one. I’ve added several in my neck of the woods, e.g. 1, 2, 3, 4, 5, 6, 7. Many of these are local landmarks, have historical significance, and may have legal protection against modification or demolition. The houses themselves are known by these names, but they are not part of an address system that includes a house name, so addr:housename isn’t appropriate.
Generally we don’t add names to houses because the houses don’t really have a name, but where they do have a name: feel free to add it!