Restrict what Apple TV content is shared

I've figured out how to share movies bought on Apple TV. But now my kids aged 5 and 9 have access to all movies we've ever bought.

One would think that the kids Icloud accounts, that have information about their age, would be able to filter PG content on their devices.

I haven't found a manual way of filtering what movies they have access to on their devices.

Is this not a feature, or have I missed something?

note: I do think the "screen time", Family Sharing and other settings on the IPad and IPhone are very unintuitive and difficult to use so I might well have missed it.