As long as I get to hurt people and not just dance around at the equinox

Lo 'tis the solstice to be jowly... or something. Give me a break, I've been an athetist since fifth grade. Christmas tunes are just earplug advertisements to me.

But hey, it's the 21st of December, meaning the day has (sadly) ceased decreasing in length and that horrible blond bully, the sun, will once again be stalking more and more of our waking hours. Unlike arbitrarily celebrating putative birthdays of putative stars of the bronze-age hermit circuit (like Jesus) the solstice is a verifiable cosmic event, a parabolic axial cha-cha with a dip every six months. You don't want to know what snow represents in that metaphor.

But hey, I already did this rant back in 2012 so let's skip to the part where I hate seasonal content in computer games... except I already did that rant later in 2012. I also stated that players in persistent worlds should be more in touch with those divinities they're tapping for spells-per-day, and that an in-game calendar could easily replace the inane grind of daily quests or log-in rewards to encourage players to keep logging in day after day.

For now, just assume the ideal of a consequential in-game calendar for an MMO, completely independent of "real"-world timekeeping, as games should be escapist fantasies and that includes escaping from choking holiday cheer. Consider how close MMOs actually are to that ideal, to the point where its lack becomes obvious recalcitrant, retrenched, reactionary electronic primitivism and not any sort of justifiable difficulty in implementation. Any MMO can already be assumed to display a "game time" clock and a diurnal cycle graphically. The sun rolls across the sky, the shadows lengthen, windowpanes flicker yellow inside all those quaint little NPC dwellings. You flip your hovertank's headlights on.

How much more difficult  would it be to link other, more practical daily events to this cycle? In the simplest terms, adjust monster spawns by the in-game clock. Owlbears respawn faster at night, treants respawn faster during the day. Take it a step further and alter spawn locations so that owlbear and treant populations succeed each other across nights and days in the same area. Sure, Warcraft 3 made a big fuss (with little consequence) fifteen years ago about giving units nocturnal abilities but whatever happened to the logical implementation of such features into the next step up from team multiplayer games: MMOs?

How much more difficult would it be to count these half-hour ersatz days and track their accumulation through an in-game calendar? Plenty of status effects are already applied to all characters within a given zone or during a particular in-game event. Why don't we have "winter" or "autumn" status effects which affect the effectiveness or access to various magic, or fuel consumption for our hovertanks? Why can't I as a druid drown my enemies in the spring thaw?

How much more difficult could it be for mobs to... get mobile, with the seasons, shifting across the landscape, migrating to warmer climes for the winter or switching into different life stages? Why not fill valleys with owlbear eggs in the spring, owlbear cubs in the summer, ravenously growing owlbears in the autumn and hibernating owlbears in their dens in the winter? How hard could it be to lengthen and shorten days and nights as the virtual year wears on? Why shouldn't darkness spells be strongest or weakest at the winter and summer solstices, respectively? Why shouldn't No Man's Sky -like "extreme night-time temperatures" freeze your science fictiony hovertank on Hoth like it did the Germans' tanks in Russia? And why shouldn't this danger increase as nights grow longer?

All this would greatly enrich persistent online worlds (and small isolated examples do exist) while requiring little to no extra character models or interface improvements or special effects or... Or jobs for parasitic code-monkeys afraid to render themselves obsolete, who would much rather justify their existence by churning out expansion after expansion of completely dull, static content than breathe life into their creations to grow and move with the tides and seasons.