the calfee has to have the exact sizes of bamboo to fit in the sockets. that would really limit the material used. a little uglier but far more flexible may be the way to go. but I bet the bamboo would give a pretty smooth ride.
I think they still make fly rods out of split cane bamboo but that is a whole bunch more sophisticated then the bike shown. Bamboo has quite a few of the characteristics of graphite. But since it is so labor intensive to make, it is far more expensive. They used to make bicycle wheel rims from wood and those worked well but were also labor intensive.
There aren't many bikes I would call unattractive but now I think I have seen one. The concept seems just a bit too primitive to me. But more power to anyone that would rather have one than a CF bike at that price.