Purchase Sharing is not actually sharing, but subscriptions are?
I've added my husband to my "Family" and we can both see that I'm the organizer and he's an adult. On both his iPad and his iPhone, he can see that I'm sharing my Arcade and Apple Music subscription with him.
I have Purchase Sharing turned on, but that doesn't show up on his devices. What I mean is that when he looks at what's being shared with him, from me, Purchases do not show up in the Family Sharing page. It's as though purchase sharing is turned off, but it's definitely turned on.
iPad, iPadOS 15