Indeed, abstraction goes all the way down, and electrical components like resistors, capacitors, and transistors are abstractions. The components themselves are

Indeed, abstraction goes all the way down, and electrical components like resistors, capacitors, and transistors are abstractions. The components themselves are largely different configurations of the similar materials and subject to the same forces. Eg, every resistor is to some degree a capacitor, and an LED, a transistor, and a solar panel are all variations on the same technology (and you can usually abuse them to fulfill one of the other roles). The distinctions are a structure we impose to create an environment friendly to engineering - abstractions.