An article recommending the use of a case would not get that many clicks I guess.

There is no material and definitely no electronic board that survives the g-forces of falling onto an edge from 1 m. That's why smartphones need bumpers. With premium smartphones you may get away without screen protection as the screen surface of those devices appears to be unscratchable like diamonds. But the g-forces on a phone hitting the ground will crack such a screen nevertheless.

And concerning heat dissipation I would like to see data supporting the claim that cases are hindering there.