There is always something better coming out. Not to say the stuff we have is bad because somethings, like my galaxy S4, will last a long time because I won't need the new features. However, as performance and speed increases means that electronics outdate very quickly and some people really do want the new shiny thing. I find that spending a little bit more money on electronics to get ahead tends to last much longer.
Another problem with biodegradable electronics I can see is some of the metals used are either toxic or something we should be recycling anyways. While it be neat to see the plastic waste be reduced, it doesn't prevent the other waste from contaminating the environment. At least it is a start but not a full solution.