I think tegra-next is coming at the right timing for something big! From the smart car presentations seems that this chip will be very powerful and will be able to compete with the Intel Core i processors on the CPU side and even beat them on the GPU side but it can't be used on smartphones because it is power hungry and the demo on the smart car required cooling fans. But I see another big opportunity for it. From the collaboration of Google with Nvidia in the past (Nexus 9, Pixel C etc) I can make a wild guess that the next Google Pixel 3 Chromebook and other premium Chromebooks could use it. Especially now that Chromebooks will run native Apps from Play Store and they will explode in sales! And don't forget that x86 chips still have compatibility problems with some apps from Play Store.
I won't be surprised to see next Christmass the Pixel 3 with Tegra-next. I definitelly would buy one!