GitLab conan package repository fails to support download for binary packages, package files missing

I’ve encountered the very similar bug described in Metadata is lost when exporting package to nexus and installing it. · Issue #5123 · conan-io/conan · GitHub

I have created a conan package via GitLab CI/CD and everything looks fine. Also header-only packages work. BUT the package files themselves are never offered. Everything looks fine, yet I’m missing the conan_package.tgz file when accessing the digest via the GitLab conan API as depicted in Conan API | GitLab.

And therefore a conan download or conan install fails.