I think it can give a false sense of security, because all of the security and privacy feature can be individually bypassed by the user.

if you try to use it the same way as a regular android phone you end up giving all the apps the same level of control as they would in stock android eventually.

what the other guy said, plus, speaking entirely about a graphene phone vs a voice assistant, even the sandboxed telemetry is going to give more telemetry because you carry your phone around and use multiple apps, but a voice assistant is a static location and most people use it for music, recipes and weather, whereas more people are more likely to use their phone for banking, shopping, maps, messaging, photos and looking at adult content.

Obviously if you have a phone you've just turned on for the first time and you like to tell Alexa when you're shopping for expensive jewelry every day it'd be reversed - I'm just talking generally

Edit to say: people get tunneled into "Alexa is a microphone, a phone is a computer" when they are both both those things.