We use preheat from the app all the time on our Leaf. In the 5 to 10 minutes of preheat the car is warm but the steering wheel is never warm if we forget to turn it on. So no, ore warming in lieu of a heated steering wheel is not a substitute.
It’s not a deal breaker for us in itself but we would consider doing an aftermarket....if there was one.
The big no starter for us is the lack of Chademo. I doubt it’s an issue for most but in our province a Tesla has pretty limited use without Chademo, or at least in the parts of the province we travel. Like I said, probably not an issue for most. Hoping they sort this out though.