In any version (snapshot, release, release candidate, or pre-release) from before the 23w41a snapshot, the snapshot realm feature does not work, barring the use of snapshot realms for older versions. You end up receiving the old error message (client is outdated)

To replicate:

Go to the installations tab in the launcher and create an installation that is from before 23w41a. Launch the game in that installation. Click the minecraft realms button, and you will be greeted with an error message. If you do this with a version from 23w41a or later, you will not be met with this error message, and, if you have access to a snapshot realm, you will be able to use it as normal.