This seems more a social convention thing rather than something that must be enforced. Requiring subpages might prevent users from doing some unique things, such as making a newsletter called "Daily weird wikipedia article", which once a day selects an arbitrary "weird" wikipedia article as its issue to forward to all its subscribers.

I think that the restriction makes sense, but we can leave the discussion for later, when we have more real users around, to check better whether there is a need for this.

From our meeting today:
<qgil> any objections to moving https://phabricator.wikimedia.org/T104570 to "After deployment in Wikimedia"?
<tonythomas> yeah - that should be after deployment, yes
<qgil> tinajohnson ? the task is assigned to you

No objections :)

Actually, more than a year later I think @Bawolff was right. There are many valid use cases where pages could be collected without being subpages. I propose to decline this task.

In T104570#1586519, @Bawolff wrote:

This seems more a social convention thing rather than something that must be enforced. Requiring subpages might prevent users from doing some unique things, such as making a newsletter called "Daily weird wikipedia article", which once a day selects an arbitrary "weird" wikipedia article as its issue to forward to all its subscribers.