This is design 101. We've been Poka-yoke-ing connectors in other industries for decades.
In fact, if you look through the datasheets for most components you will quickly realize that being able to survive reverse voltage is actually somewhat rare
Because you're supposed to build it in Most components only do one thing and do it well. You build your own protection circuit. The ECMs we use at work will take 1000V on any pin. Could you imagine how far your car would make it without any protection circuits built in?
Poka-yoke illustrates this connector pefectly - USB-C works either way so it doesn't matter which way you plug in the cable and which way it goes.
In fact, USB-C to USB-C cables are not the issue. It's USB-A to USB-C cables which cause the issues.
As for your ECU - you build them to those specs, but you pay a lot more money for an engine computer. Try to build your ECU for $5 and make a profit and you'll probably compromise a lot of things.