Sorry for the big wall of text, I’m just reading and trying to collect my thoughts and understanding of the matter.
No worries you made some good points. I was curious about the Content and Services myself. I felt like I kind of hit a wall when encountering that and trying to learn more.
Someone else stated the emulator protocol section might be referring to Valve’s functionality and network communications and if that’s the case I feel like projects like X Link Kai that allow you to remotely play LAN games on various consoles would fall under that. I do feel like it’s likely referring to things like the Goldberg emulator. I wonder if you talked about it enough in Steam forum threads if you would get banned or if it would be like all the guides out there for older games that require some kind of no-CD crack to run.