I think chris adams is the one to talk to about that. He's generally in charge of that, especially the Qt side. He's also generally in favour of large changes like that, though we haven't had the resources to do that since long before I started. He's australian - all the Jolla core Qt guys are.
they have a caldav/carddav community meeting fairly regularly, which is growing to include most pim middleware. a guy from the community called damien caliste recently implemented GPG signing in all that - so change is definitely possible. we're trying to alter things so it's easier for such things to happen.
sure i understand. still a lot of users out there though!
probably because there really isn't a suitable replacement yet
i've got a plan to integrate a proper smartwatch api into sailfish - these basic functions of notifications and calendar sync are common to all of the, plus other remote devices that might want to sync.
there's an asteroid os watch coming out soon, and people are asking if rockpool could be a base to support it