My source at Eastman Kodak - who definitely would know!
Apparently there is no known practical way to modify the normal sensitometers in a way that will allow them to both produce and measure those low light levels in a way that is sufficiently accurate to produce repeatable and consistent results.
And there is no business case for spending the $ necessary to research, design and build such a sensitometer themselves.
No, they are sensitised exactly for the purpose they were intended. Nothing "too" there. Using surveillance and aero film makes them not too sensitised but used outsided their specs.
Maybe a dumb question, but couldn't a person get basically the same effect as an ortho film by shooting a panchromatic film through an red-blocking appropriate filter?