Thank you socalpk for attempting to solve the problem, I will try those and see if they help.
As a long time Apple user, I find this change bizarre. Like most people I don't follow the evolution of iOS very closely - I use Apple because I expect their stuff to mostly work without having to look too deeply 'under the hood', and because it's nice to look at. I have I think 12 iThings in use by various family members. I'm not sure how many Apple IDs we have, I've never got Family Sharing to perform any useful function, and our calendars don't reliably merge. Contacts seem to kind of spread themselves around our devices by osmosis. I back important stuff up independently because I don't trust iCloud to do what it says on the tin, or at least not over an extended period without Apple changing the terms at their own whim with minimal notice. I imagine that makes us typical Apple users. I've never read the terms and conditions on any Apple device, nor on a message board, and I'm not going to start now.
For those of you banging on and on about not sharing Apple IDs, I get what you say. I'm old enough to remember when IT departments could impose stuff like that from the top down and take your access to the mainframe off you if you didn't obey. The world isn't like that any more. People pay a lot of money to Apple for these devices, and in return we expect them to listen when we say we don't like something. The most basic function of an iPhone is to be a phone, and the privacy of that between family members is not a trivial matter for all sorts of good real world reasons. This 'feature' that we are discussing fundamentally changes the way that function is carried out. Clearly many people don't like it, and a few do. If they have any sense, Apple will make it an option rather than erratically automatic soon, and those of us who have no desire to track our children's phone history or to share our own will be happy.
But please, 'expert users' don't keep telling us we're doing it wrong. Explain it nicely two or three times at most, we're grateful for that input. If our refusal to comply annoys you, feel free to ignore us. My ramshackle approach to managing my Apple devices worked OK, and now it doesn't. That's Apple's doing not mine. I have a life to live and I'm not going to put any more time into messing about with yet more IDs and passwords to make things fit with the current flavour of the month at Cupertino. I could throw all those iThings away and buy alternatives, but I'm not made of money, I don't believe they're any better, and Apple has cleverly tied us all in to various subscriptions and commitments I haven't got the time or energy to unpick. In return I expect Apple to sort the most obvious bugs quickly when they happen. If you're listening, can you sort this one for your customers, please?