I get that you don't need a digital calendar. I've really not ever had that many issues syncing our team's calendars between mobile & desktop clients. Perhaps I've had good luck.
It seems your argument against a digital calendar holds for all the things you're seeking a non-Google replacement for. In light of that, do we really need email or blogs, or federated IM, for that matter? Write a letter instead.
Indeed. Paper calendars might have worked for WWI and WWII, but that took a lot of effort and was not instantaneous. I would also like to get up in the morning and not have to actively check the calendar to see what are my daily tasks -- rather, I would passively glance at my phone (or computer) and have it tell me what are my daily tasks. It's just less overhead to worry about, and freeing some brain cycles for whatever tasks you may have ahead. It's either lazy or efficient, whatever you prefer :)
It seems your argument against a digital calendar holds for all the things you're seeking a non-Google replacement for. In light of that, do we really need email or blogs, or federated IM, for that matter? Write a letter instead.