"Loading time" needs to be considered unacceptable by industry. It's really blatant. I was at a Subaru dealership, ready to plunk down on a brand new 2015 Impreza, when the guy told me they all have the touchscreen infotainment setup. I asked him to show it to me. We sat in the car, he turned the key, and the first thing that showed up on the screen was... a loading bar. I walked out and bought a 2011 Mazda.
Making me wait when I didn't have to before isn't acceptable. I don't have to wait with my "dumb" TV. I don't have to wait with my non-infotainment car radio. Whatever benefits you think your new product has, introducing load times makes it instantly unacceptable to me.
I found this funny because the fourth generation Mazda MX-5 (Miata) is being released this year and just the fact that it has an infotainment system jutting out of the top of the dash is causing a lot of criticism.
It's tricky because the US gov't is mandating backup cameras soon. I'm not opposed to that, per se, but car manufacturers have taken it as an opportunity to shove touchscreens into every car. Since they need some sort of screen for the camera anyway, why not slap in this infotainment system we spent all this money on?
But yeah, I'll never own a car with a TV screen in the dash. I'll stick to the used market if I have to. I've heard some manufacturers are sticking a small screen in the rear view mirror using some see-through mirror trick. That seems like a much better solution than what they did to the Miata.
Edit: Actually do you have some links to that criticism? Is it in the press? I'm super interested in the new Miata, but the screen really is a deal killer and I wonder if enough negative press would cause them to reconsider or change it for future years.
To be fair it's only being criticized heavily by Miata enthusiasts on sites like Miata.net or Jalopnik - those that want a pure sports car experience. They only account for a tiny fraction of the people who actually purchase the car.
It's not really the idea of the infotainment system that's the problem, it's the implementation. As you said, the rear view mirror would have been better received by those who understand back up cameras will be mandated but still don't want a big "iPad" on the dash. As for Mazda's infotainment system - I believe it's the same system as used on the Mazda 3 and 6 so you can look reviews on those vehicles.
Making me wait when I didn't have to before isn't acceptable. I don't have to wait with my "dumb" TV. I don't have to wait with my non-infotainment car radio. Whatever benefits you think your new product has, introducing load times makes it instantly unacceptable to me.