I haven't yet found anything I want to do that I can't do on the HomePod natively or with shortcuts. Our home was built in 1811 and has thick plaster walls and is 2 stories over nearly 5,000 sq. feet....hence 5 HomePods bought over time at discount. So yes, some of us do purchase multiple HP's and have a good reason to do so. However, I can now stand anywhere and just say "Hey Siri" and a response is almost immediate. "play everywhere" fills the house with wonderful music and, as as someone who loves music, have found Apple Music to be more than sufficient in quality, breadth, and genre. I know sound is subjective, but I prefer the HP sound to my Sonos surround sound for all music, with Sonos being great for TV and movies. It is still amazing that I can have a smart home with HomeKit in this old house. I guess I don't need a smart speaker for much other than HomeKit, Podcasts, AudioBooks, and Music; Weather, Travel conditions, and simple factual information; and all that works great on HP. I order online....phone,iPad,desktop, or laptop....in order to compare prices and read reviews or look at menus, rather than just asking an assistant to do it.
Can someone please tell me what the objection is to having Siri answer on multiple devices or on something other than the HomePod? That happens all the time to me via HP's, AppleWatch, MBP, MAC, IPP, and iPhone. But it seems like Siri sorts out which device needs to do what seamlessly and the requested event occurs. It doesn't bother me at all. It just works.