That's a valid question. I'm not comfortable doing so for a few reasons:
YAML::Any is distributed as part of YAML. This is a module, not an application, so it might run in an environment where YAML is not available. I could certainly specify YAML as a requirement, but requiring installation of all of YAML just for YAML::Any seems like overkill. If YAML::Any were standalone, then I would have no reticence in requiring it.
As I read its code, YAML::Any won't use an already loaded module. I've decided that's an important thing to do.