Google's thing is even more stark because it had no primary raison d'etre so I only ever saw one in the wild and it was at a google employee's home!
Apple went the other way, making a speaker that you could also talk to. Of course Siri is such crap that it's fundamentally "un-sirious" too.
But speech is not a terrible adjunct. I often use speech to control my watch (start a workout, set a timer, what's the weather outside) bc the screen is so tiny and the controls so few. It sometimes tells me things if I am wearing airpods. But I have the watch cranked down to only provide me with a few things, mostly by glancing at it after it taps me. And who would design a tap-only interface?
Honestly, Kindles aren't that different. I like them (and my iPad) for traveling but I'm not sure ebooks have been the revolution that some thought they would be.