Unfortunately, mobile processors seem to still be undergoing the same rapid increase in power that desktop systems used to, and the OSes and applications are being built for top-of-the-line phones. Even my iPhone 6 struggles with modern versions of iOS, despite being under 4 years old.

It's designed for a very different use case, where power is a primary concern.

Not so if the same CPU and stuff were jammed into a car (under condition that the heat is taken care of so it doesn't throttle itself).