That's entirely plausible, and it depends on the environment. My point wasn't to focus on that particular phrase (the choice of which may vary by environment), but to more generally suggest that phrases that might seem semantically empty may in fact have a purpose beyond making something come across as less blunt.
The higher-level point: you're trying to produce a certain reaction in the reader/listener, and every word and phrase you use will contribute to that reaction. Even if you don't care about how they feel for its own sake, there's value in producing the reaction you want and avoiding the reaction you don't.
So, in my case, I've had direct experience with specific choices of phrasing producing undesirable results (and in a way being insufficiently direct), so I've adopted other phrasings that produce the results I do want. The specific things that work for you may vary.
> Also, I doubt that surveying 10 random business people what "take a step back" means would result in 6+ out of 10 defining it as "higher-level concerns". It seems like "take a step back" acts more like a discourse marker.[2]
In the specific context of the whole phrase ("Can you take a step back and explain your goal here?"), I'd consider it semantically meaningful. I wouldn't be surprised if it gets used in semantically null ways, as well.
But even if it were simply a "discourse marker", that shouldn't be automatically discounted and deleted either. To make an analogy to another form of behavior: I've seen a lot of hackers follow a certain counterproductive chain of reasoning regarding fashion. "This makes no sense and shouldn't be a thing that matters. I'm going to treat it as a thing that doesn't matter." (It's a form of the is-ought fallacy.) As opposed to the rather more effective reasoning: "This is a real social signal that turns out to matter, even though I don't think it should. It costs me little to play the game and obtain the results I want."
I'll freely admit to using empathy both because I care about other people and because I've in practice found it incredibly effective.