I'm somewhat for the IRC solution, is something I would rarely, actively engaged in, but see as beneficial. Whether it makes the game look alive or dead depends on the playing community, and does have a social maintenance requirement as well.
The longest games that would work on matchmaking, I think, would be the supreme commander FAF forever community.
I wonder if there are third party drop-in applications that can float alongside the game, or if the Unity shop has some form of code pack to simplify the implementation. Blizzard was able to float its client across all its games, which is probably a very involved task of splitting the networking layer into Battle.net and then hooking it into the social interfaces within every game. Arcen does not have a universal launcher, and will incur a development cost for the initial startup and however they choose to host the service.
Chat Latency can also be an usability issue in an age where everyone takes the internet for granted. The max we are familiar with is calling the other side of the world, which is ~0.5 seconds. Arcen might not pay for high priority traffic
to send via and receive messages to all connected players in real time.., will 3 second delays be okay? 5?
At which point should we all just install Discord and have Arcen's official blessing of a completely independent solution?
How many people will be willing to actively participate in chat while playing? Rather than browser the forum and Netflix while waiting to refleet? With the pacing of classic, there wa certainly plenty of room, and the game has pause, after all.