Per MSFT - When you revise a product and change the properties, Dynamics 365 Sales internally creates a new version of the product and copies the product details from the existing product to the newer version. The new product version has all the details including price lists, product relationships, and properties.
So if a new version of the product (via revision) is created to associate to a product family, does that mean the old version associated with open and closed orders, opportunities, etc. are not associated with a product family? Does the 'old version' of the product inherit the properties of the new version?