That’s easy. It is renewable and recyclable. Wood insulates against cold and hot and noise. It is strong, it provides structure and finish, it has substance. It dampens vibration. Wood is beautiful, and it feels good to touch.

Wood/epoxy construction is state of the art. It combines modest weight with great strength, long life, and reasonable cost. It is used to build giant wind turbine blades and giant boats, structural beams and sailboat masts, airplanes and rocket ships. But it is not just for big stuff. It is used to build skateboards and snowboards, and surf boards, and kayaks, and bicycles.
Aluminum and carbon fiber are both lighter than wood, but unless they are very thick and heavy, they both require some kind of underlying framing. Think skin and bones. Think rattles. Wood is both skin and frame all in one.

And you can hug a tree but who wants to hug a pile of aluminum ore?