If HT were to ever do a F2P planeset, which he won't, so all of these posts are completely pointless
OK. That's his call. It may be that AH is feature complete and now just LTM (long-term-maintenance).
I can see no likely scenario to reverse the downtrend if no material changes are able to be considered. If that outcome is acceptable then yeah, don't bother considering any changes.
Seasonal fluctuations aside, the player population appears to decrease every year. The player base is hitting that demographic cohort where they are dying off at a much faster clip. That will only accelerate with time as the players are probably heavily weighted in the same age range. It doesn't appear there are many new younger players being added to replace them. If just managing that downward glide slope is the plan, then yeah, don't bother considering any changes.
Failing that I can't see much low hanging fruit that he can do himself without new art and modelling. Is there a better option to increase the number of players in the area that I am missing?
Vulcan? That could help, but it might be a necessary but not sufficient condition kind of thing. I think there are too many other friction points for that to make the difference by itself, but not that I am against it.
It may be like Iron said that he has made to decision to give up and let it fade.
Maybe advertising. Maybe they can set up tables at air shows and give out t-shirts to rando's walking by.
Maybe there is some secret wonder weapon being worked on in the HTC Skunkworks that we don't know about that will total change everything and blow us all away. Maybe. We wouldn't know because HTC does a lot of things well, but communicating the long term development roadmap to the player base isn't one of their talents.
It may be like Iron said that he has made to decision to give up and let it fade. That is not an unreasonable decision for a 20 yo game. It's on hospice care now. It will never get better. It's as good as it will get, and only decline further from here over time until it is finally gone. If that is the case, the community should all probably just admit it openly and move on to acceptance stage of grief.
It's a pity. There is a core code base of simulation that has been worked on for decades that should be able to be monetized. It's a shame to just let it all bit rot.