It is solved only for some definitions of solved.

If you load 2 modules that try to load different versions of the same module, the result can be best described as "interesting". Sometimes it will work, but I wouldn't want to trust it. If that module happens to be a binary module that loads a C-level library, your chances at even limited success drop drastically.

I firmly believe that a lot of work will go into making versioning work like the spec says, and then people will discover that trying to use the feature causes far more problems than it solves. Unfortunately they will only discover the problems after having committed themselves to the strategy for a while, and so will have created some nasty messes first.