...and get junior-level advice for your money!

I think there's some straw-manning happening in the Reddit comment. I don't know anyone who uses LLMs daily who writes such facile prompts. It's simply the same advice as everyone else is giving: GIGO. Garbage in, garbage out. The quality of your results depends on the quality of your prompt. And even then it depends on which LLM you're using.

If there's any prompt-writing advice that is less commonly seen that is worth sharing more than anything in OP's remarks, it's this: instead of asking for something or giving commands, start your LLM-related work with an open query like: "Here's {a collection of facts and circumstances outside my usual skillset}. What do you think?" With the big LLMs you typically get big-picture responses of the good vs. bad variety, and most of the time, I get ideas I hadn't considered. It's the rubber ducky tactic, basically, but if you're careful not to inject much presupposition in the original prompt, you actually hear back from ducky more than you told it.