CAN communication has been around for decades on cars. I don't see that changing anytime soon. With CAN there are multiple modules (computers) communicating back and forth. And there are multiple CAN lines. ACAN, BCAN, CCAN, LIN etc. They all talk to each other through direct communication or through a gateway that connects one CAN line to another. Vehicle systems are integrated to each other. If a module sends out a message for a specific data input, the modules that receive that message either use it or ignore it, depending if it is pertinent to the receiving module. Diagnosing CAN can be a challenge at times. Sometimes it is straight forward. You measure voltages, usually hi CAN at about 2.6 volts and low CAN at about 2.4 volts. When you find the place where the voltages go haywire you've found your failed module or compromised wiring or other component. Sometimes it's a bad gateway. Sometimes it's a bad ground. It takes understanding of the sysyem and an ability to read a schematic to determine where the fault is. Just becaust there's a fault code saying PDL module CAN error doesn't mean you replace the PDL module. It meand diagnosr the PDL circuit. So many people think that a code tells us what the problem is, when it only points us in the direction of the CAUSE of the problem. I had one car a while back with multiple CAN errors. After disconnecting system after system and checking voltages, the CAN system came back online when I disconnected the engine control harness. Then while disconnecting different components of the control harness I found that the a/c transducer was broken, shutting down CAN communications. At that point I was told "oh yeah, the car was in an accident before this all happened". That information may or may not have helped in the diagnosis, I don't know. But it just goes to show that something many would consider insignificant can be the cause of a lot of problems. And if you know how to diagnose it, it isn't some magical thing that is put there to stymie anyone. It's just how the industry is moving and has been moving for many years. I remember people cussing GM's HEI distributors because they didn't understand how a pickup coil and ignition module worked. "Give me a dagonne set of points! They are foolproof"! Yes and you had to replace them every 20,000 miles. Can you imagine how many miles of wiring are saved by multiplexing sysyems between modules on modern vehicles? If you had to run separate wires for every circuit on a modern vehicle the wiring harness would be enormous. And the $3,000 harness for whichever sysyem in the vehicle would be at least double that. If there was enough market for a simple vehicle with minimal electronics, that vehicle would be manufactured today and selling like hotcakes! Tha matket just isn't there. Sorry for the long, rambling rant, just what I know from day to day experience in the industry.