As I've pointed out elsewhere, the reasoning behind it is that most game mechanics tend to be balanced towards a certain number of days, as implementing new forms of seasonal scaling is a messy process. However, in most cases I can think of, mechanics that use real-world length tend to be to the player's benefit, because the player's ability to act with or against said game mechanic is fixed. A (poorly-implemented, but valid as an example) example is spoilage of non-perishable foods. The player starves at a fixed rate and only has so much time to gather food, so in theory using real-world spoilage rates is good for the player. Of course in that example, numerous problems cause the effective shelf life of long-term goods to be unrealistically short.
The biggest issue with this is the farming right now can't really be untied from seasonal-scaling without problems. As it is now, at 91-day seasons, crop yield tends to be rather low, but at 14-day seasons it's more than enough if you grow it in quantity. However, there is a big issue with decoupling it from season length: winter has a habit of killing crops. So that means that if the sole exception to "no seasonal scaling" is removed then either the game mechanic needs to be overhauled (and not in the way the since-then-reverted farming overhaul tried to do), or you have to remove the option to change season length.
As for 91-day seasons, sometimes I do that and sometimes I don't. For the most part I'd be okay with it, with the sole exception of succession games. Those are MASSIVELY bogged down by 91-day seasons.
In other news, due to the mutation types PR being merged, while I'm still waiting from Kelenius to expand its usage in the JSON, I've implemented a little thing I'd had on the backburner since not long after I first became a CDDA contributor. Because mutations can get broken as hell if you implement a full line-by-line override (which is not even remotely futureproof), modding in mutations is a risky endeavor. But mutation types basically means you can set cancellation without having to touch vanilla mutations.
So, now another bit of random lore has an in-game representation in Arcana:
The Dragonblood Sacrament.