As far as I know they only release hotfixes for things which cause crashes. Fingers crossed it isn't a month until the next bugfix patch though.
I don't think this is true for Paradox on the whole. There don't seem to be any day 0 hotfixes for CK2, but I can find multiple instances of a hotfix on the same day, or a day after, a new patch which don't include a crash fix. For example 1.6.1 and 1.28.1.
Considering how central the marriage game is for Crusader Kings, I think this might well warrant a day 0 hotfix. The only issue is that I think pushing patches is more complicated nowadays due to games no longer having only a single platform (Steam) so it might take some more time and effort to push a hotfix.
- 2