Yep. If the original poster said something like " I took the car to a shop but they need more information. " I would gently explain the differences between a short and an open. Instead he went right for " are they stupid? "

A person can be competent in their field with recent technology but unaware of obscure more or less obsolete tech, that does not make them a dingus.

If one put a professional automotive test driver in a Ford Model T they would have a difficult time making it move let alone getting it started if they never drove one. ( A T is operated way different than a more recent car )

There are too many people that call mechanics stupid but at the same time feel that they should know every minute detail of a 40 year old car.

I've got 40+ years in and around the car business coupled with 20+ in factory automation / industrial machinery. Robots , PLC equipment , CNC lathes- mills , stamping presses , press brakes , hydraulic and pneumatic systems are far and away easier to setup / diagnose / repair than most any car from the mid 80s and up.