I think it's important to note that this is a pre-release in form of the first release canidate (thats what rc1 means). These binaries should be used to test the release, not necessarily for production deployments as they can still contain bugs.

Companies or projects relying on Bitcoin Core might want to update a part of their infrastructure to v28.0rc1 now (and other release candidates later) to be sure they are compatible with the release. The hope is that bugs and other problems are catched with the release candidates and not the final release!