I think its mostly DM style. What you allow as a DM, affects your players' thinking/creativity. A DM open to reasonable suggestions grows the PCs to think further than their character sheets. ...
No problem with making the players think. But my problem is, that I thought their tactic to be silly, not creative. Just think about the time it takes to make a pyramid and the required training to pull it of in this situation.
They could have backed away slowly, or try to climb a tree or something.
A bear is predator, not prey, so I think an attack on it (throwing stones) will have another outcome than making it flee.
You cannot have rules for everything, there is advice for the DM in the DMG for that and the group and DM play as they like. To have everything codified is just rediculous.
A set difficulties for checks appropriate for the danger of the situation (challenge rating) would work.
As an example - how would you have liked the DMG/MM to have catered for the bear encounter in my adventure? Because it sounds like you asking for the impossible.
This is actually a pretty hard question. Maybe some difficulties how hard it is to influence the creature?
How I would have handled the exactly same situation:
With the pyramid tactic, which I consider bad and silly (sorry), intimidating the bear, I would set (in 5e terms) the difficulties to intimidate the bear to Extreme (DC 19). If they had tried to intimidate it by loud shouting, waving with sticks or clapping clubs against the tree, I would have set it to Advanced (DC 15).
If one had not made the pyramid, but had used the same time they need to do this, to make a fire, his difficulty would have been only moderate (DC 11). Would you have been satisfied by my decision?
But no, the guides cannot give you guidelines which tactics are good and which bad. You have a point.