I think they could be, and not just because i think active speakers sound better...
I've got a laptop which i use as a source, most people also have a laptop, or pc, tablet, phone etc, though not all of them are using them as a source.
I've got an Apple TV3, it only cost me e109 and is simple to setup (i currently can't play video from it but that may be another thread later) and works off the bat with iTunes, receiving the audio data from my laptop, so simple, cheap and convenient.
I've got a pair of ADMs, which means i don't need anything else to enjoy excellent sounding music, i've got a complete hifi system that consists of two speakers and a tiny box, if you don't include the laptop (or tablet, pc etc.) that'd be here anyway.
Surely as technology advances, more and more people are going to end up with a similar system? Why pay for stuff you don't need? Is your typical box swapping enthusiast going to be phased out? How long will it be profitable for manufacturers to make "old skool" seperates? Economies of scale and all that.