I don't really post often but I wanted to jump in this discussion if I may.
People can have a different definition of "dead". To some it means the game lacks a reasonable capacity to progress or improve further. Which in this game, I personally find true. [ Stale metas, worst balanced maps out of any RTS game I've ever played, RNG being unreasonably powerful enough to spiral things out of control ]. For others it's just about numbers, " if the game has "X" many players then it can't possibly be dead" sort of argument. At the end of the day, the meaning of this statement depends on the person.
But let's make a few things clear. The numbers people often quote from steam charts count EVERY person that launches the game, it doesn't mean they are playing multiplayer against other users. In fact, a significant amount of them are doing campaign, case missions, ardennes assault, playing vs AI, also doing automatch with other players vs AI, working on mods, ETC. ETC. Another thing, 1v1 is most definitely dead. Just go to spectate and count of the number of matches at any given time. I would estimate there are no more than 200 UNIQUE players playing this game mode. This is pretty abysmal for a RTS game released in 2013 when you compare them to older games like WCIII, AoE, ETC. Higher player game modes are a little different because they require more people to create, so they do have considerably more players.
Let's examine another aspect. As others have pointed out, there is no comparable alternative to this game besides the older rendition of vCoH. This is the only RTS franchise with these unique mechanics. It's very sad to see that such a relatively easy to play RTS does so poorly, but perhaps that's more representative of the RTS genre as a whole.
Oh, and one more thing. I doubt the majority of people would play this game if it wasn't placed in the WWII historical setting. What else would allow people to endure such horrendous balancing and support if it weren't for the historical enthusiasts
my 2 cents. peace