Speakers obviously come in all sizes and shapes, some are monopoles, others dipoles, or even a combination of the two. If one design was clearly superior then most buyers would gravitate towards it. Maybe not though since marketing and sales have a huge impact (just consider the mediocre headphones that sell in large numbers).
Herein lies the problem. Too many myths exist so I often find audiophiles looking for answers in the wrong places. One of those myths is that a 2-way design will have better integration than a 3-way based on the lower number of parts and greater simplicity. True, a 3-way is more complicated to design; however, the drivers are operating in a more conservative fashion (narrower operating ranges) so when executed properly integration is actually better. All other things being equal the 3-way usually wins because of lower distortion and better dispersion.
The second myth is that the crossover point locations must be at certain frequencies, or to the extreme that no crossover should be used so that a single wide-range driver is the only alternative. I've found that where the crossover points fall is secondary to what is best for that particular combination of drivers. To answer those that like the single-driver concept, well, the physics weigh heavily against that approach. There are some drivers that can do amazingly well from about 150hz on up to 20K but I've never heard a system that was convincing tonally, had good bass extension, or let alone dynamic enough to compete with conventional lower cost 2-ways.