I'll throw this out – for whatever it's worth. There may be multiple ways that Apple could change things to make them more acceptable to the people complaining in this thread. For instance,
- Stop call log sharing entirely. I don't think Apple is going to do this, because they clearly see it as a feature. (Including in the context of integration between Macs and iPhones.)
- Provide a way to turn it on and off (similar to the on/off switches for other iCloud features).
- Share call logs, but provide a filtering control (in the Phone app on iPhones, and the FaceTime app on Macs) which makes it very easy to filter calls. E.g., "All phones", "This phone", "(XXX) YYY-ZZZZ" (where that is a number associated with one of the other iPhones that is using the same Apple ID.
It's not a privacy issue or a security issue. Not when you are sharing the same Apple ID between personal and company phones and potentially mixing up all sorts of other personal and corporate data.
It's a user interface convenience issue. What we really want to get to here is the requirement – not something masquerading as a requirement, that is actually a broken implementation of a requirement. It seems to me the requirement here has to do with the display ("can I easily limit the display to calls involving this phone?"), much more so than with the sharing of data between two phones belonging to the same person.
Formulating the requirement that way allows the possibility of multiple implementations, some of which may be much more acceptable to Apple than breaking call log sharing because "that's the way it was before." Perhaps Apple could be convinced to see a filtering control as a way of enhancing the call log sharing feature, while the posters here could be convinced to see it as a way to get unwanted entries from other phones off their screens.
I'm not going to predict what Apple will or won't do – just to suggest being flexible in what you ask for.