History keeps repeating itself. That is what they said about those new fuel injected motors and control systems. It's just lag as the knowledge of how to fix new things spreads to the aftermarket. The stories about the Prius/Toyota battery pack corrosion and the DIY fix (instead of a complete battery pack replacement per Toyota standard operation) are an example of this. There is always a group that resists change and says it's the end and then within a few years, people adapt and figure out how to fix things all the same.

Admittedly, if completely locked out of the control system, what Tesla is doing may be more effective at blocking the aftermarket. But at some point, someone will just rip out the whole processing unit and replace it with a homegrown solution. The refrain has been "oh, all these sensors and who knows and ...". But the aftermarket keeps getting smarter.