Ah that's fair, I forgot how old the Model S is comparatively. Although in a normal car of that era (say a 2012 Kia Rio) you could add CarPlay today for about $220.

It's unfortunate that the big tablets have made it impossible to upgrade features like this anymore. I had bluetooth audio units in two cars that long predated standard bluetooth. Now the screen is too central to the operation of everything that you're stuck with 2012 capabilities for the life of the car. Some features added by $3000 infotainment computer replacement, but only what Tesla wants to give you, which is still not CarPlay.

Slate IMO is going a little far by not even having built-in speakers, but hey at least whatever system someone decides to add to it doesn't need to last 20 years and can be swapped out without losing the air conditioning controls and the backup camera.