That takes quality at both ends, and that aint cheap
A poor subwoofer integrated with tower speakers won’t sound good either. So assuming your buying a good subwoofer no matter what, then you can get likely get awesome sounding bookshelf speakers for the same price you could get good sounding towers.
I think towers are a much safer bet on music because the tower is designed to be intergraded fully down to the bottom of the tower's range.
One of the assumptions I made was that the bookshelf+sub combo was based on a multi-purpose system. I agree that adding yet another crossover to the mix complicates things but even for music an integrated sub+bookshelf system can often outdo towers in many if not most untreated rooms do to more flexible placement options allowing the bookshelves to be best placed for imaging and the subwoofer for flatter bass response.
Again there is a valid if not somewhat esoteric argument for stereo bass. But without using treatments and something like a BFD most people would likely get better results by using multiple subwoofer placement to even out the bass in their room while using bookshelf speakers for their often better spaciousness and sound imaging potential rather than using towers or stereo subwoofers.
Good luck figuring out what range was missing in the two second sound blurb that bounced through that range in a movie score.
Assuming your using a subwoofer for HT as most people do then you still have the same potential for missing information at the crossover to the subwoofer with towers as you do with a bookshelf speakers. The tower does give you the option to use a lower crossover and push any potential missing information lower but it’s still missing, plus bass room resonance issues start becoming more complicated when playing tower full range.
Clearly there is no one correct answer but for most people (maybe not be those of us who hang out on audio forums) buying tower speakers is likely a waste of money, and due to placement constraints and costs may not sound as good as a bookshelf + subwoofer solution.
