"Doug Perovic, a professor of materials science and engineering at the University of Toronto, said that carbon fiber was a bit like a diamond: strong while not being particularly tough."
"What results, Perovic said, is that when a bike is stressed beyond its limits, it “fractures into many pieces while metals bend, the energy absorption is the bending.” While steel and aluminum bikes generally telegraph an impending failure by displaying cracks, carbon fiber generally fails without warning."
"Greve and Perovic agreed that for consumers who are not constantly banging their bikes around on team vehicles"... [an interesting way to put it when considering current events] ..."and who are unlikely to be involved in crashes, the risks in buying a carbon bike made by a reputable company should be minimal. Greve said many riders had told him that the performance gains from superlight frames reached the point of diminishing returns long ago, and he questions the wisdom of consumers’ buying what are, in effect, very costly throwaway items if they crash."
Ductility versus brittleness. Use materials within their means and you're a-okay. Understand and choose wisely.