Composites in aircraft applications require a lot of heavy duty engineering, design skills and testing. Even then, there are all kinds of things that must be avoided to prevent premature failures and unexpected events.
For example, during the various Airbus and Boeing projects using composite components, such as the A320/321, A350, A380, and 737, 757, 787, an astonishing amount of basic research preceded any component design work just to quantify various processes associated with structural composites.
Here's a informative paper on the impacts of composites compared with traditional materials, things that most folks wouldn't have ever considered become critical under some conditions that don't affect traditional materials.
Safe operations with composite aircraft | Safety First
I have studied some aspects of composite design, and I'm pretty sure that Al Kraft has experience in this field as well. Mine goes back to working for Kaman Music, the original parent company of Ovation guitars. I spent a good deal of time studying the process and the potential pitfalls regarding the manufacturing process which came as a byproduct of Kaman Aircraft which was a very early adopter of structural composites in high lift helicopter rotors (which were inter-meshing). The backs of the Ovation guitars are manufactured using composites, not just for weight (which there was no real world savings) but for the ability to create shapes that were impossible using traditional materials, as well as for increased consistency and acoustic properties that all owed for them to be the first practical high production volume electric-acoustic guitar suitable for touring in high stage volume environments.
My experiences strongly suggest that if impact resistance is accounted for in the design so that the cabinets are as impact resistant as plywood, and that the joints and corners are as strong, the weight and cost increases to where much of the benefits disappear. The other issue with composites, especially manufacturing in California, is that the hazardous materials (handling, permits and disposal) can be shockingly high and these must be accounted for in the final price. Time will tell if the process becomes more environmentally friendly overall which might change these metrics down the road.