Shared albums not appearing across all devices on the same iCloud account

The iPad, iPhone, iCloud account and Mac are all on the same iCloud account and share their data with each other quite happily, but with photos, it is not that straightforward.

Photos are shared, as are any albums I create, regardless of which device I create them on.

However, if I create a shared album on the iPad, it shows in the iPad and iCloud (web) account, but nowhere else. I create a shared album on my iPhone and it appears in the iPhone and iCloud account but nowhere else and, similarly, if I create a shared album on my Mac, it shows in the iCloud account and the Mac but nowhere else.

Is there a rational explanation for this and if so, what is it, please?

I also have noted that neither the iPad nor the iPhone can Airdrop to the Mac - the icon is there with the Mac's name but "waiting' is the only thing that happens. Are the two issues related?

Screenshot of the iCloud shared albums is attached.

Cheers, with fingers crossed.

[Edited by Moderator]

Original Title: Sharied albums not appearing