GitHub offers two options for storing container images as I understand it: Container Registry and Packages, but I think the difference is not clear. In a blog post, they say "With GitHub Actions, publishing to GitHub Container Registry is easy." but the given example pushes images to Packages, not Container Registry.
So, can those two platforms be used interchangeably and does one have an advantage over the other?
As already stated by tgogos the GitHub docs guide on Key differences between GitHub Container Registry and the Docker package registry tells us:
The GitHub Container Registry supersedes the existing Packages Docker registry and is optimized to support some of the unique needs of containers.
TLDR; The GH Container Registry will replace the Packages Docker Registry. It also focusses more on the GitHub organization level then on a single repository. So you find your container images on the account level for example - and have to link them optionally later to a repository if needed. Additionally it features anonymous access to Docker images (see the GHCR intro post here).