I'm glad somebody else notices this. One accentuated low-frequency resonance point, who does this impress? And there's just a stupid amount of music tailored to this basic deficiency in speaker design: DOOMP-DOOMP-DOOMP-DOOMP-DOOMP-DOOMP
one of the requirements for good bass reproduction is that the woofer needs to move a large volume of air, and a lot of what passes for subs, just don't do that. it's rare to see subs with a woofer larger than 10" these days.
The above can be seen before buying on some drivers in the thiele small parameters, the important ones being VAS, QT and resonance.
Max cone excursion is also usefull on designs with smaller cabs.