There are clear distinctions between the approach of Solidworks and something like ABAQUS, which maybe be throwing you off a bit.
Solidworks FEA is designed to be "push button" and aimed at design engineers. There was a vision that FEA could analyze CAD models simply and hence the material database sped this up further. It may have also been there for those who did know where to find material properties or be familiar with them (which is a scary thought). To be frank, this did not work well and any stress engineer can tell you the many problems associated with this approach.
Now enter ABAQUS (or Nastran, Ansys, etc.). A good FEM model and understanding behind it requires a good knowledge of material properties and how they are used. If there was a material library, I think most real stress engineers would bypass it anyway. They want complete control and could care less about built in libraries. You should already be familiar with you material system, its behavior, etc. before you be begin analysis.
So while I do understand where you are coming from, it is not something that I would find useful. I can't think of another true stress analyst who would find much use in a built in library. Everyone would rather enter in their own data, considering effects like temperature, statistical basis, plasticity, etc. This probably takes less than about 1% of the analysis time.
The other thing is that a stress report will require you reference the material property source. I don't think anyone would "believe" the built in code. In addition, how would you know that the material properties are up to date? Most stress reports will have a section that specifically discusses the material properties. This is part of the analyst's job, and not the job of the FEA software.
Brian