Earlier quoted context omitted.
That's extremely broad. I know how to push the buttons on my washing machine. So now I'm a laundering engineer? Maybe the answer is "yes", but I think it's a bit silly, and detracts from the engineering work that goes into building the machine, i.e. the work of understanding the connections and flow of electricity from button press to pumps and gears turning.
The person who shoveled coal to a steam locomotive was called a railroad engineer. I guess the distinguishing feature here is how much capital is tied to the process and how much value it creates - not how intellectually demanding it is as such. If you had a button that switched on a thousand washing machines at a time I guess one could flirt with the title "washing engineer".
Since that button probably wouldn't work correctly 100% of the time, the operator would probably be forced to learn about problems and solutions related to that activity. Over time, that person would accumulate experience and knowledge which would make them well suited to that simple job of flipping the switch on and off. And at that point, that person would be more of an engineer than a random person who walked up and flipped the switch.
An _anything_ engineer is just someone who does that thing and the unnamed related things necessary to do the main thing.