CLI save-as saying it can't save

I am trying to use the CLI to export a set of tags as gifs.

I have the console opened in the directory where the file is. I run the following command:
aseprite -b animated_tank.aseprite --save-as animated_tank_{tag}.gif

And I get the following back:
Animation>Aseprite can't save "./animated_tank_." file ("")

The name of the animation file is: animated_tank.aseprite

Aseprite Version: v1.2.29-x64 (Steam Install)
OS: Windows 10 Home
Version: 10.0.19043 Build 19043

I tried running this in a PowerShell terminal and I got this failure. When I ran it using cmd it worked. I’m not sure why it worked with cmd and not with PowerShell. Seems strange.

I’m leaving this here in case someone else runs into that behavior.