I am not sure if this is an issue or a feature request, but I have noticed if I have an excel formatted xml file, you can open it with the excel com object and then save it out as an xlsx, but ...

An XML map allows a business to arrange data stored in XML documents so that the information can be easily imported into a predefined table in an application such as Microsoft Excel. In this way, the ...

Universal Business Language is an open library of standard electronic XML business documents for procurement and transportation such as purchase orders, invoices, transport logistics and waybills.