The OP is suggesting to replace the term PMF with "extreme growth" or something similar. Obviously that would be wrong, because you can certainly have PMF while also not reaching extreme growth because the Market part of the PMF acronym may just turn out to be really small. For that reason, it's always been clear in order to achieve extreme growth, you have to have PMF and a large addressable market. So, no, for me personally, I wouldn't see much value with introducing a new term to describe the confluence of both, market size and PMF, and I certainly wouldn't want that term to be called "extreme growth."