The python-any-r1 eclass is meant to be used for packages that have build-time dependency on Python. The generated || dependency (and lack of explanatory USE flags) is not appropriate for packages that require Python at runtime. Please fix the package to use python-single-r1. While at it, please remember to include PYTHON_REQUIRED_USE in REQUIRED_USE.
I believe this was fixed by QA in this commit: https://gitweb.gentoo.org/repo/gentoo.git/commit/app-admin/syslog-ng?id=5ee8c6f1f65e5f854790e50d25bfc9c19a2c7ac3 If I'm wrong please re-open