Certainly it is true that subjective preference depends greatly on the perceived amount of bass. However the notion of "more bass" is not sufficiently well-defined to be useful in an objective sense, beyond subjective perceptions. As you certainly know, the bass rolloff in a sealed speaker is less steep than in a ported speaker. With ported speakers, the mechanism by which the -3 dB point moves lower in frequency is that the "knee" of the rolloff becomes sharper when the Q of the rolloff is increased.
You wrote, "I don't really understand your point about output an octave below the tuning frequency. That would necessarily be 24 decibels down and not very important." After reading this several times, my sense is that it is not sufficiently precise to warrant serious consideration. I will however say that on a great many occasions I have heard extremely high levels of distortion from ported speakers, subwoofers especially, the likes of which I have never heard from any acoustic suspension speaker. While it is difficult be entirely certain that the frequencies in question (the fundamental frequencies) are below the port tuning frequency, I don't think there is sufficient good reason to assume that all of it was driven by fundamental frequencies at or above the port tuning frequency.
The mechanisms are reasonably well understood. In the vicinity of the port tuning frequency, power compression occurs in connection with the fact that the resistance to air flow in the port increases as the square of velocity. This is typically a strong contributing source of distortion, roughly par with distortion caused by the trailing end of the coil leaving the gap at high excursion. Below the port tuning frequency, driver excursion is barely controlled. Theoretical output is derived in consideration of the fact that the output of the driver and the port are increasingly out of phase as frequency decreases further below the port tuning frequency. This theoretically derived output is far removed from a theoretical estimate of the level of distortion generated with fundamental frequencies below the port tuning frequency.
All that said, I do not think your express intent was to say that ported speakers are "better" in an objective sense. Your intent was perfectly within reason. People very often say and write things that seem perfectly innocuous, in web forums especially, but without giving a lot thought to how what they write will influence how other people think. You wrote something that seemed perfectly innocuous and reasonable, but it encourages other people to adopt the dogmatic belief that ported speakers sound better than acoustic suspension speakers, in an absolute, objective way.