I guess I'm not entirely surprised you would weigh a radio as significant criteria for picking a vehicle. But then again this is one of those rare instances where I partially agree with you.
Toyota's Entune system leaves a lot to be desired and the new "Entune 3.0" system doesn't look like much of a real improvement, if not a copy of other systems (don't get me started on very convoluted data function 3.0 is supposed to introduce, I forsee a lot of issue on the tech side of that). Given that most people like shiny things and what's more shiny than a big screen with pretty lights to distract you while your driving, I can see a very throw-away consumer oriented populace being drawn to the shiniest of screens.
Though last I heard the Linux side of it was supposed to be more open-ended and more developer friendly? Though it would not surprise me if they did change their mind again in that regard.
Honestly everyone just needs to standardize and make these infotainment systems an open system that owner's can choose (i.e. if they want to use a Crapple-based system, let the idiots use it. They want to **** with an Android system, whatever). Hell just make it easy, "you use our manufacturer specific OS/package we'll warranty you/support you, you want to use something else; you're on your own. Simple as that, there'll be people that stay with the Toyota stuff and there will be people that won't; who cares about the latter (from a manufacturer standpoint).
The biggest thing is that most manufacturers are not very bright when it comes to structuring their infotainment systems and some are so bright as to give them far too much control on the CAN bus (*cough* Chrysler *Cough*), but that's easy enough to code for and throw a firewall module (which Toyota has started doing). But that's not a significant issue to prevent an open-ended system. It's just a stupid money grab on the manufacturer side and given how many ****ing software updates and headunits I have to replace because of how idiotically close-minded they are in regards to this set-up I vote just make it all open source and be done with this very closed minded eco-system; make's Apples totalitarian and stagnant App Store seem like an ideal free market.