There are a multitude of reasons, but I think the biggest ones are (1) the unfamiliar syntax; (2) the fact that Lisp runtimes tend to want all code that interac

There are a multitude of reasons, but I think the biggest ones are (1) the unfamiliar syntax; (2) the fact that Lisp runtimes tend to want all code that interacts with it to also be Lisp instead of focusing on FFI and interoperability; (3) Unix and C were free and so went viral.