Collecting all that data is harmful simply because it can be assumed to be hacked at one point or another. Massive potential for misuse by criminals or authoritarian governments.
Is it still pretty good for you? My wife and I have been having sync issues with shared lists. A few zombie items (we ended up both buying coffee for home, not the worst thing), and a few items not syncing for days. This started maybe around the iOS 10 upgrade?
The Dalai Lama fought most of his life for the right to cultural identity. It's exactly what he is asking for here, that one society doesn't get its cultural identity destroyed by an influx of individuals from another society.