I'm not familiar with Julia, but from a Common Lisp perspective it is very natural to closely link OO and function dispatch. Generic functions were added to lisp as part of its object system and make up a large part of it.
Indeed! My first OO course at the University of Minnesota (1992 or so) was object-oriented programming using Scheme (using SICP). I was more of a C++ programmer at the time and the different perspective was eye opening for me!