I seemed to recall this being reported earlier, it being discussed, and a fix being created.

And indeed, a change was made to the serialization component to optionally force the values to be objects rather than lists: https://github.com/wmde/WikibaseDataModelSerialization/commit/83e999983149c7163c9853c6ff3376287fd96fc1

Funnily enough this option is not used anywhere in the actual Wikibase extensions, which means the behaviour is entirely unchanged. Looking at the relevant code in the serializer [0], I do wonder why an option was added, rather than simply always using an object. Is there a case where we want objects when there are entries and a list when there are none? And if so, should that really be the default behaviour?

[0] https://github.com/wmde/WikibaseDataModelSerialization/blob/master/src/Serializers/SnaksSerializer.php#L69-L83

Cheers

--
Jeroen De Dauw - http://www.bn2vs.com