Wood turns up in some very surprising & unlikely places industrially for armour, insulation, wear resistance, flexibility and sheer strength. A good example is the skid on the tail of commercial airliners which drags on the ground sometimes during take-off. Generally they are made from Oak and it beats metal or polymers in almost every respect.

Contrary to what you might think, it survives longer in fire than steel (it retains more of its strength).

One reason it's not used more is manufacturing cost - it's hard to mass produce a wooden item cheaply.

Maple Ply, as used for skateboard deck s has useful strength and elasticity properties. Whether it's marine or not doesn't make much odds unless you are worried about it getting wet.

Sensibly designed, a wooden robot could have a lot of advantages. But, the devil is in the detail.

Si