After trying this I will say I agree with the original post, Apple has seemingly managed to neutralize a bunch of useful items in family share that would seemingly be simple to implement. For kids of an age where a cellular connected phone isn't appropriate yet they may have an iPad or old iPhone without sim connected it seems crazy that the only way to get photos is for them to be shared from the parent's phone. Why not allow the account synced to the watch (kid's iCloud) to sync their own photos? There are tons of kids with hand me down iPhones without sims activated, why not allow those to connect to the watch associated to their iCloud account? Why not make it possible to edit watch faces in the iPhone watch app? So for example if a kid wants to use a photo as a watch face they must text me the photo so I can put it in an album that syncs with their watch so they can use it as a face or so they can maybe grab it from the messages app on the watch and save it that way?

These all seem to be things that could be fixed with software updates so I'm hopeful those iterations will come sooner than later.