There are very few who support one but not both, BMW most prominently (CarPlay only).

my 2016 VW Golf supports Carplay, AndroidAuto and a 3rd solution (like Miracast but for autos).

Our Skoda Fabia does both.

Yes Chevys do

My experience is the same. For day to day, bluetooth phone<->car connection beats Carplay or Android Auto. Wireless autoconnect is key, should've been in the V1 of those standards.

I never bother with Carplay for less than a 1 hour trip.

We use CarPlay all the time, it works almost instantaneously after plugging the phone and it is always responsive. The primary beef that we have with it is that you cannot use Google Maps. Though Apple Maps is definitely many times better than the built-in navigation system.

As you say, it is probably a problem with some hardware.

Eh, it’s instant on in my car (a Citroen) but I suspect they start booting the electronics when I unlock the car. In the 3 months I have had the car it have never crashed but twice CarPlay refused to find the phone and required a reboot of the phone.

Aside from the startup time, I don’t have any of those problems. I love CarPlay and would not consider buying a car without it

You need a better, stronger lightning cable for your car. Apple OEM cables can’t take the wear and tear in a car. As long as my lightning cable is good, so is CarPlay. You can also go the wireless route as an alternative