I love that.
You keep back-pedaling regarding the premise of the OP and you'll end up falling off a cliff.
The so-called high sensitivity drivers are so because they have less throw and power handling. This makes them far less useful as subwoofers, which is why they're never used as subwoofers except by folks like yourself who seem to have a penchant for wishful thinking.
Siegfried's L/T throws HIL out on its can, making the box irrelevant regarding 'low cutoff point'.
You've done nothing but model some of the latest drivers. Going back to Hoffman's contemporaries was a great suggestion. A review of Ed Vilchur's AR-1, the first acoustic suspension speaker:
Julian Hirsch, who at the time published the Audio League Report, wrote that 'the AR-1 had the lowest electroacoustic efficiency of any loudspeaker on the market - but at 25 Hz and below, it was more efficient than the Klipschorn, which had the highest efficiency of any speaker on the market.' Hirsch also said that the AR-1 'established a new industry standard for low distortion bass.' Eventually, the industry began to realize that the smaller size of the cabinet was only a secondary advantage of the extended bass response."
At the time, Bozak was reaping the benefits of HIL (as he had been since a decade before HIL) as a dictate, and actually sold IB systems in kit form:
The CG's large (52" H by 36" W by 19" D), massive, particleboard enclosure is designed to be as close to an infinite baffle (a large wall) as possible. In fact, Bozak sold many Concert Grands in kit form where the buyer supplied the enclosure—a wall of the house. (Imagine the wife catching you drilling 14 good-size holes in the living-room wall.)
That's 22 cubes vs 1.3 cubes.
What you're trying to say here is that the 2 men could have traded woofers and saw no difference below 40 Hz.
The difference in Fs, 1W/1M and Cms between the drivers Bozak and Vilchur was huge, unlike your computer model, which features all low compliance drivers of the same basic design. Same goes for the arbitrary selection of box size, an amplifier that can somehow deliver pure sine waves to DC, assumptions regarding power handling, suspension linearity, flux modulation distortion and many other factors.
Omegaslast has it right. What is the sensitivity of a driver in 'x' box at 5 mm past its Xmax? What is the sensitivity gain in a driver installed in a system that's designed to maximize sensitivity gain vs any driver in an arbitrarily sized and shaped box... in actual use? There are a hundred more similarly rhetorical questions before your case is closed.
The suggestion that "all sealed subs are the same... cased closed" is as silly as comparing CHT's Eminence drivers to the Maelstrom-X, XXX, LMS-U, UXL-18, FTW-21, etc., which is the actual premise of the OP. It didn't fly here when it was originally injected and it doesn't fly here now.