In the great majority of cases, this stuff tends to last essentially forever, or if it fails it fails early on. This is certainly true of low-voltage logic circuits. The power stage less so, but that stuff is generally repairable so big costs are less of an issue. Remember when fuel injection was new, and everyone was terrified of the huge cost of replacing the FI computer? That was a new technology and there were (a few) failures. How often do you hear about an ECU failing now? The high power chargers and controllers on EVs are not new tech, that stuff has been around in the industrial sector for decades. Not only that, I believe the charger and controller electronics are considered part of the vehicle's power train, and subject to mandated warranty coverage like any emissions-related component on an ICE.