There is also a related TODO in WikibaseRepo::getStore():

// TODO: the idea of local entity source seems not really suitable here. Store should probably
// get source definitions and pass the right source/sources to services it creates accordingly
// (as long as what it creates should not migrate to *SourceServices in the first place)

Observation from the change dispatching hike: the single-repo assumption is still deeply wired into the whole change dispatching system. This will require more than just cosmetic cleanup.

As far as I can tell, this entity source is mainly (only?) used for two broader concepts:

• the site link lookup
• change subscription and dispatching

The site link lookup actually feels like it could use the item entity source instead (as long as there’s only a single item entity source…). The change subscription/dispatching is related to T293354: Support dispatching changes for entities in non-main slots, I suppose, because MediaInfo would be the first case in Wikimedia production of a client getting different entities from different sources. (Federated properties don’t support change dispatching at the moment, and that would be a wholly different thing anyways.)