JMich: Unsure. The example of CKII being used recently, it seems that the base game can be played just fine without Steam, but the DLCs depend on steam to be accessible. Not sure for their other recent games, or their older ones.
Trilarion: And the number of DLCs is quite large. They are a substantial part of the game. But then what does it mean to say "Steam is DRM" or saying "Steam is not but Steam's DRM is DRM". We all know what is meant by both. We shouldn't nitpick the words too much except saying that some games are without DRM on Steam.
tfishell: I don't think of Steam as DRM necessarily, but I don't like Steam's "monopoly" so I try to support GOG within reason.
Trilarion: You mean, Steam has no DRM or Steam's DRM is not really visible or you don't care much about Steam's DRM?
Steam itself just provides games like GOG, but the client is like a cloak to cover up the fact that you can play many of these games directly from the .exe and "distract" people from pirating, if you will.
I'd consider the client DRM if indeed offline mode still has problems, IE it
needs to connect every day, but it can just be a tool to make game management much easier.
I'm kind of just rambling but for your question above, I'd say
it depends on the game. With GOG, though, you get (as I like to say)
openly DRM-free installers - much easier to pirate but more consumer-friendly for those who don't like Steam's client, or have spotty internet, etc.