A dynamic language with optional static typing is still a dynamic language that offers its own syntax for dispatching to statically typed code. Python originall

A dynamic language with optional static typing is still a dynamic language that offers its own syntax for dispatching to statically typed code. Python originally offered easy dispatch to C++ code, and Groovy to Java code. The typing guarantees aren't really in the dynamic language there if it's optional. There's also the commercial aspects of static typing in a dynamic language. After 10 years, Groovy introduced the annotations to optionally statically compile code in order to compete with Java instead of complementing Java, which changed the business purpose of the language and their relationship with Oracle.