A 5-way speaker system is a lot of cross-overs and driver segments to handle, in vital frequency ranges at that - that's certainly where the complexity part comes into play and getting it all to mesh well, let alone seamlessly. The active platform per se on the other hand is not what I'd regard "complex," that is to say: similar amps could be chosen above the "power region," and the active XO should make the integration part that much easier (and, I'd expect: better sounding) compared to a passive approach.
I think you wrote a lot to my simple point: Multi-way, active crossovers do not in anyway guarantee a significant audible improvement even when done well. That a 5-way, active crossover system is not really a selling point so much as a design choice.
Having said that, it sure simplifies things as a crossover designer to work this way.