Note that this narrow definition of Linux leaves out the leading touchpad implementation: ChromeOS. If you wanted mac-like touchpad performance and Linux, you could have had it for many years now.
It's not really a narrow definition of Linux. When the vast majority of technically-oriented people say Linux, they mean Linux with some sort of GNU userspace like with Debian or Ubuntu. It's even hard to install Linux on some Chromebooks...it's hardly a Linux experience out of the box.