Earlier quoted context omitted.
But that's not a gas vs. electric distinction, but rather an old vs. new one. Modern ICE cars have all of those problems too.
Yeah, its the same stuff that I've been told for decades now. TBH, it is probably less true with a lot of EVs than it was with the gas cars. ECUs are pretty strict and sometimes hard to hack. Meanwhile, third party motor controllers for Tesla motors exist, and the batteries aren't exactly magic. There's really nothing about electric drivetrains that makes anything vastly more locked down.
A lot of diesels can run off of any vaguely fuel-like liquid you decide to put in them, so I'm sure sufficiently knowledgable people would keep those running, machining parts for them etc.
But electric vehicles are by far simpler than both of those, and generating electricity is easier than producing fuel you can shove in a diesel engine.