I think the spark plugs example is an excellent one. People used to require an extensive knowledge of how cars worked in order to have a prayer of using them effectively. Now they don't, because we realized none of that knowledge is necessary if you design the system correctly.

We have enough historical context to realize that things like parsing URLs by eye is unsafe for the general population, and always will be. The solution is to engineer that need out of existence.

You might want to consider that manufacturers have added blind spot detectors to cars as people are bad at changing lanes safely, even with all the training in the world.