That has nothing to do with a commercial perspective. We are constantly adding features into our open source KNIME Analytics Platform, if you are watching our changelogs it always contains more feature for the Analytics Platform than for the Server. We just recently released MetaData Mapping it would have been easy to not implement this for the Analytics Platform and only for the server, but we always follow our Open Source Story
The server enriches the features of the KNIME Analytics Platform with productivity and enabling collaboration. This feature already exists on the server, where it does make sense to ensure easy recreation of older versions. There is no architecture available in the Analytics Platform which would allow us to easily add this. However, I would definitely recommend making a backup of your system regularly.