It wasn’t restricted to your primary account originally. My wife and I have our own primary icloud accounts but we also share a second one that we use for all Apple, iTunes, and App Store purchases. Which also gives us a second email, Reminders, Calendar, and Contacts accounts that we share. Why they restricted a second account to those four services I don’t know. We would previously add information that we both needed access to in a note in that second account, as we currently do with the remaining four account services. We can no longer do that and have to find another way get the information on both of our devices.
My fear is that at some point they may restrict those accounts even further. However there may be a specific functional reason for Notes to be set up this way since it has so many other functions.
My situation exactly. My wife and I each have our own iCloud account and we have a third one that we share for email, Calendars etc. and we also used to be able to access these joint account Notes. Then I inadvertently accepted the 'upgrade to new Notes' offer that was resented to me at some time and only later then realised this now prevented sharing the Notes of our joint account. Needless to say I tried to 'downgrade' back to the usable setup we had, but oh no, that is NOT possible. Apple totally screwed us by this change, with no warning that the 'upgrade' would have any such draconian effects and that there'd be no going back. This is Apple at its most despicable.
There is now the ability to share a Note, or a folder of Notes, but this is NOT the same thing. Think of it like bank accounts. We each have our own personal and private accounts and also want a shared 'household' account which would be used to pay for all joint, household expenses. It would simply not be the same thing for each of us to share our personal account details instead. It's not the same thing at all.
With Notes, being able to share personal Notes is a good idea, but not at the expense of both being able to access the same joint Notes account. They are different facilities and anyone at Apple making decisions about the Notes app and who doesn't understand this should not be in that position.
Any iCloud account can be used to share the other services, with only the obviously personal ones like Safari history and Key Chain being restricted to the primary account, but why Notes has been downgraded to be restricted in this way is beyond me.
It baffles me that Apple can produce such great products, then screw up its customers by making bizarre and dumb decisions like this.
