Sure, no reason not to be able to voice control all the HVAC settings. I just hadn't yet needed to adjust those while driving (currently using auto mode and so far it's not terrible), and the up/down arrows for changing temp are pretty small areas to hit without looking.
It would also be nice if I could press the button and "hey google" activate and converse with the google assistant on my phone, i.e. "hey google broadcast I'm on the way" (which will let my wife know via our Google Home (minis) that I'm leaving work and heading home, and if she wants me to do any shopping or pick up food on the way home she can call me). I can call her, but she often leaves her phone laying around in another room... though I'm not sure if this is feasible without some kind of carplay/android auto support. I couldn't do this in my previous car with BT so I'm not sure if it's actually doable.
Right now I'm just popping open the phone charge area lid, flipping open my phone (I have a flip cover on it - HTC Dot View), and then I can "hey google" at it bypassing BT.