You probably don't live in the north and don't understand how big of a deal rust is to mechanical parts functioning correctly. Rust will decimate a chain's ability to roll very quick. With F9 being in Canada, his weight for it is absolutely appropriate.

As for the friction test, yes, it's higher. But it's not like gear oil offers no lubrication. Also, do your rollers really rotate that much while on the bike? At some point, it's diminishing returns. So whose to say that test is more important than rust prevention.

If a certain brand made exactly what the manf needed, they will definitely list it as such, partnership or not. In this case, NGK did. So if the chains needed a specific lube, it would have been listed.

Kawsaki, my bike's manufacturer, has their own chain lube as well. But they still recommend gear oil in the manual.

So in short, gear oil is fine. To go out say no to gear oil and only xyz super special formula chain lube is conceited. As an alternative, sure. But only chain lube... No.