Linux isn't the problem: with enough money and time, you could build an OS around Linux that a user can use just like MacOS or Windows. Sony built an operating system around FreeBSD for the PS4 that noone recognises as such. The problem is that open source software (which Linux necessarily attracts due to licensing and reputaion) is designed by people with a fundamentally different view of ergonomics, and the number of disparate HW components (audio, graphics, etc) create a similar number of software components that make integrating them cumbersome and frustrating.