Would you tell your kid, “Don’t go near that croc.” or ” Do keep a safe diastase from that croc?”
Which is more effective? “Stay calm”, or “don’t panic.” “Be kind,” versus “don’t be a dick.” “Don’t smoke,” instead of “smoking is bad for your health.” Hard to say. I’m leaning toward framing advice using “don’t.” Maybe regrets can be better avoided using “don’t”.
If something bad happens suddenly, you’ll likely be in a state that isn’t calm, so saying “stay calm” may not resonate. “Don’t panic” addresses how you’re actually feeling in the middle of something scary.
If you’re asked for simple advice about how to conduct your life, “be kind” seems open to interpretation about the degree of kindness or to whom it’s applied. “Don’t be a dick” is not open to much interpretation.
At this point in the modern world everyone knows smoking has no redeeming features. “Don’t smoke” is good reinforcement of what everyone knows and hearing it directly is not new or shocking.
Unsolicited advice is rarely welcome, and probably seems stronger when it’s framed with “don’t.” But when advice is sought out, using “don’t” works because people often define themselves by what they choose not to do, use, or wear (it could be a longer list).
Using “don’t” is an ok route to go. Framing something by using “don’t” identifies the opposite choice, the one that shouldn’t be chosen.
Advice is sought for an opinion and not to find out about facts. An advice seeker is looking for help making a choice, hopefully a nudge that squares with their identity and worldview, not necessarily wanting to hear about the facts. They want to connect with others in their group. They want to think, “People like us don’t smoke (or smoke)” not be directed to the Surgeon General’s website.
Using “don’t” is clearer and more succinct.
Just think about how much shorter the Bible could be by letting “don’t be a dick” cover the ten commandments, the golden rule, and the like. And everyone would get it.