I agree there is a grey area, which was my intent in writing the article. My intent was also to have conversations like these. So thank you for taking the time to discuss.
I separate design practices into dimensions. Industrial designers work in the 3d space which is connected to the word product. Product by definition is “Something produced; especially : commodity (2) : something (such as a service) that is marketed or sold as a commodity”. Commodity is “a raw material or primary agricultural product that can be bought and sold, such as copper or coffee.”
I believe graphic designers work in 2d space. Even with up and coming technology, the two practices are separated. For example, the VR headset is an example of (physical) product design, while the content of the 2d viewing screen can be a practice of graphic design (depending on what interface is being made).
The conversation then is an opinion of whether language is evolving. I do believe it is, but I don’t think graphic designers should highjack terms used by other fields.