Migrating K2 database currently requires following the steps in this KB:
https://community.nintex.com/nintex-automation-57/commands-to-update-k2-database-encryption-782
The migration involve manually running some Powershell commands, which may be confusing for customers. If any of the steps are not performed correctly, the encryption/decryption will not work properly on the K2 database. Having a UI or tool to assist with this process can help prevent customers from performing the migration incorrectly.