You cannot compare a what works for a home theater speaker and a car audio speaker. They run passives because they know what crossover point and slopes work best for their drivers in their cabinets.
Car audio has wayy to many possible combinations of location power enclosure etc to try to have a preset crossover achieve the best results.
Active is not a bandwagon it really is a much better choice.
I'm sorry, but I think people put too much into what active xovers can do. For one, unless you have a really complex active xover component that can alter the xover point by really small and very accurate increments, without contributing other undue side effects, you are not going to gain much from it except for the fact that it should present no signal loss. That lack of signal loss was really the only reason they were ever introduced to car audio, and were mainly intended for subwoofers, where lack of signal loss was critical. But even if you use an active xover, and it happens to have the exact xover point your speakers require, you should probably measure the final results, as quite often these components are not 100% accurate, and even if they are there are still electrical side effects they can introduce. Someone with a little knowledge on the other hand could measure the speaker's installed response and build their own custom passive xover with a xover point that is at least as accurate if not more so, and be virtually guaranteed to have fewer side effects.
Regarding the above, how many people really know what type of quality parts are being used in the average active xover, and what influences these electrical pathways are subject to. A digital xover is even more complex and there are plenty of additional build factors that can come into play that can adversely affect sound quality. On the other hand a passive xover is exceptionally simple in comparison and often more predictable if you are using quality trusted components.
Lastly, xovers are there to simply set a high or low pass frequency cutoff point for the intended speaker, control the rate of the xover slope, and maintain phase as well as possible, not some other worldly and magical phenomenom.
So I repeat, if active xovers were that much better than passives you can bet that the home audio manufacturers would have jumped on them a long time ago. It's not like the high end home audiophiles aren't willing to spend the money on it. That’s why speaker bi-amping was more of a phase than a serious challenge to reputable system building.
Just mho.
