It seems like the author has very different needs than you.
The cobbler's children go barefoot, so I haven't come up with a good solution for us... >sigh< It almost makes me want to hitch my wagon to a hosted product/service. Almost.
Comparing a paper calendar to a digital one is like comparing a Nokia 3310 to a modern smartphone. Yes, technically both are "a phone" but that's roughly where the similarities end.
Set up a webcam stream of the calendar
How do you share it for common events with others?
Share the webcam link or ring them up on the telephone if we are (jokingly) going traditional.
Why not make it more convenient for them and pipe the webcam stream through a script that OCRs it on change (or on timer) and makes it available as an .ical file that others can import via a link?
Also it's 2025, you can do it fast and robust by piping it through an LLM instead, with a prompt like "turn this calendar image into an .ical file pretty please".
/s, but only a little :). I've honestly thought of doing that for real, except with a feed of my laptop screen, to sync availability (busy/free) info from my work calendar to my family one, because it's way easier than trying to argue the point with corporate IT.
(I've changed jobs since then, and now I'm using a lazy hack on top of some random Fastmail-friendly cloud app.)