I agree with you 90% haha, it would be 95% if you lower that 10% case of yours to 1%. Think about for instance, on AH and AVR forums, how often do people list their speakers that have impedance dips below 2 ohms and align with not too friendly phase angles, and those that do, how many actually have such conditions, dips and/or high phase angle in the band that tend to demand high enough energy to be problematic?
I am thinking in addition to your speakers, the likes of the KEF, R and reference series, and B&W diamonds that might fit the category. Not to split hair, but 10% seems highly inflated, just my 2 cents.
FWIW, not really a big surprise, I have been testing an entry level Denon AVR that has only FL/FR preouts, with my buckeye amp that has 3 dB gain lower than the AVR amps. The speakers I have been using are D.Murphy's BMR, the original version that I DIY'ed. Those speakers sensitivity are quite low, seems lower than my LS50 (also original version), so I would put them in the neighborhood of 84 to 85 dB/2.83 V top, and impedance probably around 6 ohms nominal. I encounter not audible issue at volume higher than -10 and I am confident even at -5 they would still sound fine, and that's in a 11.5X20X9' room. It would have no trouble the LS50, that lots of forum talk about them being "difficult to drive". When I drive the speakers with the AVR's amps, they performed just the same, audibly speaking, I may try to increase volume to near 0, time permitting.
As often mentioned, talks like "amps clipped more often than people know", and "for real world use, people need much less "power" (or you can change it to "current") than they think they do, can both be true. The bottom line, we need to quality any such related claims with other factors/caveats. Overall, there aren't anywhere near 10% of hard to drive speakers that 90% of forum members need to worry, we'll never know what they number is though, admittedly, with a huge survey, but I would put it at below 5% for sure, potentially below 1%.
