Why change the term? There isn’t property called unreal per say, but other types of property are personal property and intangible property (ie patents, copyrights, etc). Estate doesn’t have to be large. Estate just means the property belonging to someone. For example, someone dies and they leave property (real and personal) behind. The property might not be worth very much, but it will still be called a decedent’s estate. Another example is a Bankruptcy Estate. Often times there is hardly any property in a bankruptcy estate (not the smartest idea to file bankruptcy if you have a lot of property), but it’s an estate of property (if any) administered by the bankruptcy trustee. It doesn’t have anything to do with there being a huge house, or any real estate at all. it is the property owned by the trustee/debtor (in a bankruptcy).

I don’t think you really understand what an estate is.