Typing preferences are usually due to trends in language usage having little to do with knowledge.
Plenty of java programmers use static typing without ever having to understand type theory.
But looking to history of language designers/implementers
Dan Friedman
Gilad Bracha http://www.infoq.com/presentations/functional-pros-cons
Guy Steele
Rich Hickey
All of these guys have worked on static languages, have a keener understanding of type theory than most, and yet they seem to promote dynamic languages at least when it comes to their pet languages.