Game isn't dead but it is certainly not in the place it once was. Once Dawn of War III was announced it was pretty obvious that most of Relic jumped ship from CoH2 and went to work on that.
Yes, I'm actually still surprised after all this time CoH2 still manages to retain about 3000+ to 7000+ players. Even a long time after (what I assume to be is) CoH2's last expansion.
There's still that charm in a WWII isometric game that CoH2 fulfills so nicely.
Which the question arises do they have something in the works content wise? I remember reading an article right before WFA came out two summers ago about how Relic had a little more than half of their team actively working on CoH2 content and the rest working on "other projects" (DOW3 most likely). Now most of the team is most likely full time DOW3 with some people working on CoH2. Relic did say they have a roadmap planned in the months ahead so we shall wait and see for now. One more Axis army and a few commanders would be a good "finale" for the game.