Prompt engineering is a thing, but I wouldn't say it's much of a job title. There are people doing it: optimizing system prompts, preprocessing and postprocessing, llms are just one piece of a complex pipeline and someone has to build all that. Prompt engineering is part the boot strapping for making better llms but this work is largely being done by data scientists who are on the forefront of understanding how AI works.
So is prompt engineering just typing questions? IDK. Who knows what those people mean when they say that but whatever it's called there is a specialized field around improving AI tech and prompt engineering is certainly a part.