• I ask Homepods to play some music, and music starts playing in another room.
• I ask a room to play something, it says that is not in my library. I ask again. Same response. The problem comes in two flavors: One, I have to power cycle the Homepod to get things to reconnect. Or two, there is a halflife of disconnect where each time I ask there is an independent 1/2 chance of resolving the problem.
• I ask the Homepod to play something in multiple rooms. Some rooms play others don't. Sometimes, one room will start and stop playing randomly. Sometimes all the rooms will start and stop playing randomly.
• I ask a Homepod to play in a Zone. Same issues as asking for multiple rooms explicitly.
• Sometimes paired Homepods will both play, sometimes only one.
• Sometimes Homepods in a pair respond differently. If I carefully ensure only one hears me, it might be the one that starts the music that the other one refuses to do.
I can go on, but my experience is Homepods don't scale. A single pod or pair are much more reliable. Obviously, the more components a system has the greater chance of a problem, but it shouldn't be every day, or multiple times a day, for an integer we normally think of as "small N".
To say my Homepod use has been shaped by these failures is an understatement.
Apple has completely dropped the ball on Homekit. The app interfaces are completely ridiculous. Bad parody of bad app interfaces ridiculous.