Like all these things, sometimes people get carried away with stuff.
I can honestly say that never in my life (and I am in my 40s) have I had a need to use any version of office for anything in my car!
Having said that, from the front seat, I don't want DVD video either (I could possibly want the news if I was waiting for someone I guess).
I want a decent GPS, and arguments aside, the IT doesn't have that currently (something as usable as say a tomtom) from my POV.
I want music, and to me 32GB is enough. It doesn't have to be encoded at huge quality, you are in a car.
I don't really see VOIP as useful in a car, although phone control is handy. Not so sure about the abilities of speech recognition. If I get phoned by someone in a car sometimes I can't tell what they are saying, what chance does the computer have.
I never want to order a pizza in the car. Ever.

However, I do want the things that I would consider a car computer useful for, which you haven't mentioned. I expect it to store the radio traffic reports in case I want to listen to them at some point. I want it to alert me if there is traffic the way I am going (I guess the tomtom replacement does that). I want it to tell me how much fuel I have, and where the petrol stations are along the way. I want it to tell me what my fuel economy, range, average stats for driving.
I want it to tell me that I need to put some washer fluid in the car next time I can, or that the wheel bearing on one side of the car is over hot.

I also expect (and this will become reality at some point soon) it to slam the brakes on if I am so busy playing with the electronics that I haven't noticed the car in front of me stopped.

Maybe it would be handy if when wobbling around lining up to overtake it gives me a percentage chance of succeeding :-)

Then when I get where I am going and there is a little space, I expect it to analyze the space, tell me if it can fit in it, and either guide me in or do it for me.

Now that is a car computer. What you described is a PC put in a car for a laugh!