According to a report in the WSJ, Alphabet is considering rolling Nest back into Google. It appears that it's the IoT which suggests it makes sense, as Google has its Home speaker, and that competes with Amazon. [wsj.com...]
aside: I fail to see the logic comparing Google's Home with Amazon's Echo. Yes, they're both speaker boxes that use a digital voice assistant, but where Echo is pretty much locked into the Amazon website's services, Google's Home is so much more. It interacts with anything the Chrome browser does, which is the entire internet. I run a recording studio with Home... try that with Echo.