Voice assistants are best when they are ubiquitious.
If an assistant isn't ubiquitous they're basically just accessories to make speakers smart ("Play Kendrick", "Play Fresh Air").
Using an assistant for more than smart speakers is born of habit. Habit is born of ubiquity. To start using assistants for phone calls or adjusting the heat or simultaneous translation on a regular basis I think the assistant has to be with you all the time, like Samantha in Her).
Google recently added Assistant support to the Nest Cam IQ. Support was added by software update. We have a Nest IQ in our daughter's room and the update was welcome, but I think it represents a small baby step in Google's grand plan.
I think the next step is adding Assistant support to Nest Protect smoke detectors. I don't know whether this will require a third generation device or not, but it's inevitable.
Smoke detectors offer ubiquity in the home.
The National Fire Protection Association recommends homes should have smoke alarms installed inside every bedroom, outside each sleeping area and on every level of the home, including the basement. So that means a 2 story, 3 bedroom house needs a minimum of five smoke alarms.
There you go. Get Nest Protect. Get Assistant in every room. Get one step closer to the inevitable future of ubiquitous voice computing for the whole family. It's been a decade since the last major platform shift came with the introduction of the iPhone. Another one is coming now. Time to start figuring out what the killer apps are going to be.