Well, that's one way to look at it. Another is to say that it was perfectly clear what it meant when it was coined - redefining the idea of "product" to mean "something that gives you feedback on your plan", rather than "something people can use". It was the idea that you don't need anything more at this stage, not a "real" product.

Sure, without the history people won't understand it, but then that's true of most terms in most fields, and I'm really not sure if there is a way to prevent it.

Remember, naming things is hard.