Uh, I think you're forgetting PHP. Not to mention Clojure is at least as popular as Go. Dynamic typing isn't going anywhere, desire for 'gradual typing' is a very niche but vocal desire in the dynamic language communities. It may lose some mindshare but there are a lot of options to lose that to these days since even the holdouts of 'annoying' static typing with terrible type systems like C++ or Java are making it more and more feasible to ignore/not specify the types in your code.
Ha, you are right, I forgot PHP. However I think PHP is really a language where people agree that it has lots of weird corner cases.
So its popularity is really historical incident, in particular I think, that it was the first hack (see worse is better) to allow to easily deploy dynamic web applications (via web-server side interpretation of code, which got popular in Apache). Furthermore PHP hosting is still very popular in low-cost bundles to integrate e.g. Wordpress.
Clojure is another nice language, but could benefit from typing. :p Maybe the main "problem" for dynamic languages ist the fact that it requires more discipline on the Programmer's side, so I imagine it is popular for smaller teams, but this is hard to achieve for bigger development efforts, where you can benefit from a stronger type system.
