I recently tested some very different speakers is a large acoustically lively room that sounded surprisingly good. When my wife heard them, she went nuts. She is usually complaining that the sound is always too loud. With these speakers, she could handle near THX Reference and loved it! I thought, what the hell gives here? The particular speakers roll off at 16KHz, but have very strong mid-range reproduction. They also do not sound lacking in highs. They just don't sound harsh or fatiguing. The also have very wide and smooth dispersion. An RTA measurement across a four-seat wide area at 14' distance shows it to be amazingly flat above 400Hz (a little wanky below that due to nearby boundaries). I didn't take this as an amazing discovery of a speaker, but maybe an interesting indictment against the possible unintended consequences of speaker designs that are flat out to 20KHz.
Hiraga is a great mind from the global "Joelist" tradition (the philosophy responsible for the best DIY ever conceived), commercial audio is naturally overrun with formula product, and an inexperienced listener can indeed perceive more as better.
There is much this theory: Audio is an art informed by the sciences and genuine realism is a goal not always well-served by conventional wisdom. When in doubt, listen.
I think that my initial premise is possibly addressed somewhat by utilities such as Audyssey. In Audyssey Pro there is additional flexibility, including a target curve designed for rooms that require more high end roll off than the regular Audyssey curve. That is probably a more realsitic approach than trying to find a speaker today that will be best in a particular room/environment.