In theory, the learning based approach in this blog post could solve this without any architectural changes. They mention predictions spilling to nearby roads,

In theory, the learning based approach in this blog post could solve this without any architectural changes. They mention predictions spilling to nearby roads, learning the pattern that "if the highway is backed up now, the little road will be too in a few minutes". Once that is baked into the model, Google Maps won't direct (as many) people onto the site road because they would get stuck in the predicted traffic there. The nice thing about this is it also handles the case where other mapping applications direct drivers there, and the "smartest" mapping application will still get you there fastest.