Some players use repacks as a "demo." Since Enshrouded does not have a traditional free trial, players download the v558123 repack to test performance on their hardware. If their PC runs it well, they later buy the game on Steam.
In the world of Early Access games, version numbers are vital. represents a specific snapshot of the game's code. Enshrouded is currently in Early Access, meaning the developers are constantly pushing updates, patches, and new content. Enshrouded v558123-Repack
If you are playing a version older than v558123, updating is highly recommended to avoid save-file corruption. Some players use repacks as a "demo