Oh wow. Regardless of whatever metrics you can think of (absolute df player numbers pulled from discord, reddit or whatever) it does seem that people care less and less about the game.
It's the release spikes that worry me. On April 1st, 2010 the server went down under the load and the brothers got $10000 that month. The 2012 release gathered much excitement and the wiki was updated with research within weeks. Now the artifact release, which brought major gameplay changes, hardly made a blip. I was talking about insurrections earlier, but science on missions, artifact types, etc. is very lackluster, and it's been a year already.
People may support the game more, but they engage with it less. They go like "yeah this game is awesome and super complex and detailed and Toady is a genius" but they don't actually play it. For many people, their image of the game is the same as it was in 2010 (.31.25 or so) or earlier, so they share memes about carps, danger rooms, giant sponges, ancient bugs or ancient dogma about weapons as if nothing changed since then, further proof that they haven't actually tried the new versions yet.
That's a worrying trend, because without the enthusiasm of the 2010's, we wouldn't have gotten dfhack, therapist, armok vision, all these utilities that make the game accessible (some would even say 'playable'). If lethosor retires or decides to raise sheep in New Zealand, what happens to dfhack exactly? If newbies suddenly have to play the raw vanilla game without any starter pack, will they keep playing?
Of course, the fact that Toady doesn't play the game himself, and doesn't actually like Fortress mode (by way of various clues such as always implementing fortress mode features as the lowest priority, or his own admission in a pc gamer interview that he isn't into fort mode style gameplay) doesn't help. If you keep making a game, travel the world doing talks about your game, have your game featured in the MoMa, but nobody actually plays your game, not even you, is it really a game?