I've been researching this since seeing the debate on the other post, and it seems to me that while there's an at least very roughly agreed definition of "High Fantasy", what constitutes the opposite of it to be "Low Fantasy" is defined in different ways by different people, so I think it probably would be better to give it another name. It seems to me that the distinction you're making is between "secondary world" and "real world with fantastic elements", but I'm afraid I can't think of a particularly concise way of expressing the latter.