Not arguing for or against this move, but I find it hard to believe that a drive would just encrypt itself without prompting the user.

I turned on TPM specifically to pass this test and it's showing all of my drives as unencrypted and needs administrator approval to activate it for any of my drives.

Some computers come with it activated by default, but I'm fairly confident it's not going to just jack your hard drive for simply activating the hardware.

It should tell you what aspect of the PC isn't up to par.

It does, from what I can tell. It told me specifically it needed TPM to be activated to install and I subsequently activated it in my BIOS and passed.