VirtualBox – Enabling encryption allocates all dynamic storage

So, if I create VM with 50gb dynamic drives, and only use 20gb, why does enabling encryption permenantly expand the .VHD file to 50gb? This is a win10 guest on win10 host.

So, even if I decrypt…

VirtualBox – Enabling encryption allocates all dynamic storage

Source: [H]ardOCP – VirtualBox – Enabling encryption allocates all dynamic storage