No, I don't think I missed that point at all. Both the post that you are responding to and another one I wrote below indicate that the proliferation of rules in MMA designed to protect the safety of the fighters and to allow the sport to remain legal in the US have harmed its previous status as a perfect laboratory for unarmed combat, though it remains the best we have. Also, MMA is unarmed and one-on-one, which does not accurately depict all combat settings.
However, old school MMA and Brazilian Vale Tudo had/have very few rules. It would be easy for a master of a useful art to make his name in such arenas. Even today, I see no obvious reason why martial arts such as Karate, Kung Fu, and Capoeira couldn't be applied under modern MMA rules except for the fact that they are not effective.
It is hard for me to imagine that a truly superior unarmed martial art could exist without having some influence on MMA. No art relies so completely on groin strikes and eye gouging that its central lessons could not be adopted under the rules of the sport.
Arts that claim to be too deadly or too dirty to use in competition (such as Krav Maga) may well be useful. However because they are too dangerous or dirty, they can't show us any evidence of their usefulness. The burden ought to be on the teachers who sell expensive gym memberships to make the case that their art is useful. But there appears to be an audience for martial arts that favors them in inverse proportion to the extent that they have demonstrated their usefulness in actual combat. It is as if some people value the mystique of martial arts above all and are afraid of mixing it up with a real opponent. They want the self-esteem and ceremony of wearing a colored belt and looking good in the mirror, but not the pain and sacrifice of getting actually punched in the face.
Krav Maga suffers from the additional drawback of being a popular fad martial art, so the average quality of a gym varies very widely. Otherwise, I see nothing obviously wrong with the philosophy of the system. At least they put on padding and hit each other at full speed, which is essential to any martial art worth the name.
There is certainly room for martial arts designed to be taught to little old ladies or used under unfair situations. However, the proof of their effectiveness will always be skanty, limited to hypothesized bar situations and anecdotes. Meanwhile, Jiu Jitsu fighters prove the effectiveness of their art by choking people unconscious in a cage fight. Muay Thai fighters prove it with the blood of their opponents. The strength of the evidence in favor of arts used in MMA is much higher than evidence for arts that claim to be useful outside of an MMA setting.
On a somewhat related note - Alistair Overeem and his brother got into a scuffle with six security guards in a Dutch nightclub. They won.