I check often enough, mostly for bounties to redeem and to keep my account logged in as a training dummy. If someone wants to talk there is always the discord for people who are there, although this is a bad substitute for the game and can siphon activity from here to there, to a lesser degree the forum does this too.
A lot of the activity I used to manage was directly people related, quests run by people that I no longer have interest in rewards or activity for. Or more specifically people that I had questions for, about lore of the game or game related features, most of which the questions have dried up now.
Some specific time is an idea I had recently to spur more activity but what I learn from time based games is you often get different crowds to show up for different times, so whoever may be relevant may never be there at those times. Moreso people tend to get very small time windows that they will show up at and adjusting a time to suit any wider range of people is near impossible and doing certain tasks takes too much time. Essentially you need to find the regulars and cater to them and you will only have so many of them on average.
I think there needs to be more "daily quests" type of materials, just something to bring us here, historically this was resource gathering as those are reset daily and people would come around to gather, spells and item resets are more of the weekly type of quest. Perhaps mp6 and kingship/alliances/housing could be expanded to accommodate these types of daily activities in order for those active to participate in the related power structure.