I founds this article very interesting as the question of “what is an MVP” is one that gets people confused very often. I find that people are keen on cresting a half-done product and call it an MVP because they are thinking about a set of features, instead of thinking about an MVP as the most minimal thing to test an assumption of, as you say, the grand idea. To understand that needs a mind-shift change away from prpduct to solving problems.
Also interesting is how people think there is only 1 MVP but a list of assumptions. Again, I think this points to a fundamental misunderstand of what an MVP is in the first place.