I think you switched from a binary flag ("no true PMF ... ") to a scalar without realizing it:
> Most businesses don't have product-market fit in this way.
They'll have it to a lesser extent?
The word "Fit" kind of implies a scalar relationship, and the disagreement over who has "it" and who "doesn't" comes down to size of market and suitability for that market. Why can't you can be perfect for a small market, or crappy for a market so large that you initially succeed but plateau.
Endothermic and exothermic are different categories of reactions and both are also scalar. PMF is exothermic in this analogy. Growth produces more growth by itself, like a raging forest fire. Whereas regular business growth is endothermic: when you stop selling you stop growing.
Endo / Exo have a zero point, across which you discretely jump categories, after which you scale up or down subjectively.
PMF does not have a zero point. If you sell (clasically) "zero to one" item you may or may not have PMF. One nuclear reactor / aircraft carrier is a big deal. One newsletter subscription is a small deal.
> Most businesses don't have product-market fit in this way.
They'll have it to a lesser extent?
The word "Fit" kind of implies a scalar relationship, and the disagreement over who has "it" and who "doesn't" comes down to size of market and suitability for that market. Why can't you can be perfect for a small market, or crappy for a market so large that you initially succeed but plateau.