Richard,
I have been using iCloud in years to share some photos from common trips / events etc. with good friends.
That has worked well and I deemed it to be an excellent offer by Apple, as the sharing is much more integrated, safe and uncomplicated than using other non-Apple products like Dropbox for example.
For me as a customer, one of the strong points for Apple products / services is that they are usually well connected, easy-to-use, smart and stable.
That are some of the USPs of using Apple.
I am also willing to pay for these services, but only where it makes sense to me, e.g. for the pictures that I want to share.
So this recent step of Apple to restrict the sharing option to customers that upload their COMPLETE photo library to the cloud does not seem consistent to me, and it certainly sacrifices one of Apple's main USPs in this area.
Also, I would doubt that the only purpose of iCloud is to let you have access to your files and pictures on all of YOUR connected devices. Then it would not make sense at all that Apple offers the option to share photos with OTHER people.