Thanks to Janne252's Release of the Essence Archive Viewer, I discovered that the references to the Attrition gamemode still exist in the attrib.sga file (as of 12/08/2023):
![](https://www.coh2.org/file/20944/references.png)
As you can see, there are also references to the CoH 1 Panzerkrieg gamemode, which I'd also love to see.
The full path is:
Company of Heroes 3\anvil\archives\attrib.sga\multiplayer\match_type\