Family Sharing, iCloud Drive I remember years ago, family sharing was a cool feature but I didn't get involved with it as I didn't like the fact one had to share the same credit card / payment method, across all accounts.
Thus if I added my Wife and Son to my family sharing, they would both be using my card whenever they made purchases.
This was years ago, recently I moved to the 2TB iCloud Drive plan, and I'm now interested in sharing that resource, but only if I can keep our accounts/payment/files self-sovereign.
I searched for authoritative documentation, but can't see any.
If I just shared iCloud Drive, can I keep these aspects separate per user, whilst sharing my space?
Yes, when you set up family sharing it will ask what you want to share. You can share iCloud storage space without enabling purchase sharing, which does still require the family account organizer pay for the family purchases.
Here you can see I’m sharing iCloud, Apple Music, and Apple TV+, and Purchase Sharing is not enabled.