I think the main issue is that a lot will likely stop logging on not long after content drops stop. There will be die hards who will keep going, who will keep logging in, hoping they can be part of what keeps it a float and part of the reason why it gets revived, but I just don't think there are enough.
I've kept the game installed and played it occasionally, looking forward to new content. But tbh, I'll probably just stop playing for good once I've played the update that's coming and had one last hurrah with the clan members who are hopping on for one last tour.
Do I expect it to go to zero players? No. Do I expect it to still hit the 10-11k ccu a day + whatever the number of unique users is each day? Also no. I expect it to get cut in half within a month or two. Where it goes after? No idea, but I don't see it going up.
I'm really going to miss this game, warts and all. The highs were incredibly high, but the lows were incredibly low. Many good memories and good friends made. Even during its lows the clan members would always look forward to seeing what next expansion would get announced, would opine on where we all thought the story might go or what bits of lore we hoped would take the spotlight. Those of us who still played would salivate over upcoming dungeons and would look forward to diving into the next day one raid.
The worst part is we just went through 9 months of complete radio silence, while the face of the game was constantly telling us all "teams jamming. Wait till the road map!", and then that road map was delayed till early in the new year, and then all mention of it disappeared altogether. It's not as much it's coming to an end that hurts, but just how it's coming to an end. No grand send off, no dramatic end to the story….just a cliffhanger in a new saga, and a sad tweet. For a game that, whether people liked it or not, seized the spotlight multiple times over its lifespan and did manage to cultivate a highly dedicated fan base who loved playing it.
And in the end, it's a story of horrible mismanagement of the thing that was keeping them as a studio afloat. Re-invest into the thing that attracted such a rabid fanbase? No, they spent that money on other things. On games that went no where, on a game that could never hit those highs. And I'm not against Marathon existing. I think it's neat. I was just against them starving their golden goose in order to make it.