Adding home automation elements during construction isn't new. What's changed in the last few years is that the prices have dropped dramatically (from tens of thousands to about $3,000) and the systems can be run from Apple's HomeKit or a voice assistant like Alexa instead of proprietary hardware.
Providing homeowners turnkey solutions gives these companies an additional source of revenue. But, it also shows that the current wave of connected home devices and platforms is finally reaching a level of maturity that will convince people that home automation is actually useful.
Read more: https://www.engadget.com/2016/07/15/new-homes-with-homekit/