Except the industry is nearly dead. Almost nobody is buying legitimate stereo systems anymore, and the ones that are out there (at almost any price) are mind-bogglingly incompetent. I'm shocked that Sonos is even a going concern at this point, although I suppose it is because of what I relate below.
The home-audio market is consolidated into a tiny number of manufacturers masquerading under once-proud brands they bought. The crippling incompetence of the products themselves is depressing.
A few years ago my Denon A/V receiver crapped out and I decided to go "upmarket" and get an NAD T758. I accept a bit of quirkiness from a smaller name, but "quirkiness" doesn't come close to describing the design and functionality defects that plagued this thing. Everything from baffling menu navigation (not kidding: Pressing Enter did not select a menu entry; you were supposed to use an arrow key) to the fact that it would only pass 720p video because it reported erroneous EDID info to HDMI devices. It didn't pass the info from the connected display device; it just provided its own EDID blob to everything, which reported a max resolution of 720p.
The NAD also featured Dirac processing, which I shelled out for to get the full license and spent hours with a test mic profiling my room and speakers. Then... it would just lose the entire configuration. Deleted off the receiver. "We haven't been able to figure out why this happens," said NAD. In fact, in several years they never fixed a single one of the crippling defects I encountered and reported.
But NAD isn't the only shitshow in town. Let me address the biggest impediment to whole-home audio (or even multi-zone audio): manufacturers' bizarre conceit that anyone can use secondary zones that only play ANALOG sources. The NAD was crippled by this stupidity, as is the top-of-the-line Pioneer I bought to replace it.
In the case of the NAD, I addressed this defect by running RCA cables across the back of the receiver, from its preamp outputs to a CD-player input; and assigning that input to Zone 2. Why the hell didn't NAD just do that internally with a switch?
On the Pioneer, it's actually worse. There ARE no preamp outputs. It has THREE zones, one of which I can tie to the main one but the third, yep, can only play analog sources.
All I want to do is play the same shit on ALL MY SPEAKERS. My living-room ones, my patio ones, and my backyard ones. All I need is A, B, and C speaker switches. But NOPE. As far as I can tell, nobody makes this. Nobody addresses the 99% use case for multiple "zones." There are at least NINE AMPS in my receiver, but I can't play the same source on three pairs of speakers.
BTW, I did build a patch bay with switches, to wire the secondary zone in parallel with the first... but this overloaded one pair of amps in the NAD and destroyed the entire receiver. Yep: NAD doesn't have a simple overload breaker. They just burn the entire amplifier board up; that's the breaker. Unfuckingbelievable.
But back to the main issue: Who is seriously going to dick around trying to select sources and adjust volume to each zone (with what, by the way, an app?) on one receiver instead of simply buying a bookshelf system for every remote room you want to play music in? I sure as shit wouldn't, and I'm the kind of person who ran digital cables under my house to an equipment closet so I could have a proper surround setup in my living room. I have a projector and home-built screen, but even I would never bother with the stupid usage scenario Pioneer, NAD, and the two other makers envision:
This scenario revolves around nonexistent people who are going to put on a RECORD or TAPE, then go to the other side of their house or down to their rec room for half an hour... and then come running back to the other side of the house to flip the record or tape over. WTF.