I've switched to a #NextCloud calendar. I have a shared calendar with @Katy Lamothe, who's still using #GoogleCalendar, and while I can subscribe to the NextCloud calendar from her Google account, it's not syncing when I add or modify appointments. The problem is definitely between Google and NextCloud as her web calendar isn't updating either.

Everything I search trying to fix it has to do with Google-hosted calendars not syncing with third-party apps. It annoys me that the assumption is that I'd not want to use anything other than Google Calendar.

Side note: the NextCloud calendar syncs perfectly with her Apple Calendar, but she doesn't like it.