While it is true that there are good and bad examples of both design principles, they are actually worlds apart. I discovered about 15 years ago that you could apply Newtons second law of motion to loudspeakers, especially woofer/enclosure designs and completely understand them at least mechanically. I thought I had seen something new and then started reading Sam's Audio Engineering Reference Handbook and saw that the people who were on the cutting edge of mathematical modeling of woofer design were way ahead of me. Still many designers use cookbook recipes and apply software blindly without knowing why they do what they do.

Basically, a loudspeaker is a resonant device meaning it wants to vibrate at some frequencies and not at others. What the speaker designer wants ideally is a device that doesn't appear to want to vibrate at any particular frequency or group of frequencies at all over a very wide range of 10 octaves, the range of human hearing. To do that, not only do they use multiple drivers, each optimized for a smaller range of frequencies but they have to "tune" each one in effect optimizing it within its range. Acoustic suspension drivers/enclosures and drivers intended for ported enclosures and their enclosures are tune according to entirely different methods.

Three factors interact to play the determining role of what the frequency response will be. First is the mass. How heavey is the cone and other moving elements. Second is the spring constant which restores the cone to its neutral position after the electromotive force of the opposing magnetic fields of the coil and field magnet are removed. Third is an aerodynamic drag factor which dampens the motion. This factor is related to the velocity of the moving cone. We normally associate it with viscosity but you can't change the viscosity of air.

The true acoustic suspension woofer has a very low inherent springiness. Its spring comes from the difference in the air pressure trapped inside a sealed box and the pressure outside of the box. The huge advantage of this is that the force is independent of frequency but only dependent on the air compression or rarifaction. The drag is controlled often by fiberglass batting inside the cabinet causing the cone to have to suck or squeeze air between the fibers in order to overcome the difference in pressure. This makes it relatively easy to tune an acoustic suspension speaker to have a very flat frequency response down to a very low frequency and to fall off relatively gradually below that frequency. This means that using electrical equalization either within the crossover or at the line level, the response can be further extended to some degree. The tradeoff is relatively low efficiency but with advances in making powerful magnets for speakers in the last couple of decades, efficiency has improved.

Ported designs use drivers with mechanically much tighter suspensions which are needed to restore them when the electrical signal applied to them is zero. The enclosures are designed to reverse the phase of the sound coming from the back of the cone so that it is in phase with the front wave when it emerges from the box. The enclosure also has a port or pipe inside which acts much the way the pipe in an organ or reed or wind instrument works. It has a column of air inside which is very easy to move at some frequencies and not at all easy to move at others. The frequencies of "resonance" depends on the length of the pipe. The resistance of air and hence the springiness of the resistance to the woofer's movement becomes a very strong function of frequency. The speaker is very efficient at the "tuned" resonant frequency and at multiples of that frequency but very difficult to move at frequencies in between. It is extremely difficult to overcome this phenomenon. Because the resistance to moving air changes so sharply when you move away from the tuned frequency, ported speakers are considered to only be useful down to that frequency and not below it. To get this frequency very low requires an enclosure with large dimensions and so ported speakers that are reasonably small generally don't have the ability to reproduce the lowest tones you can hear.

There is no reason Japanese manufacturers cannot make outstanding loudspeakers. In general though, they don't seem to have. A notable exception is Yamaha NS 1000 which has a cult following and is a collector's item. I am sure in the future, Japanese high end manufacturers will catch up and produce some of the top rated models.