This was in use as a statement-value on several Commons files, as part of an exercise to map out ways to model appropriate structured data statements to describe the origins / source-nature of material there.
Please discuss first, before deleting items which are in-use as statement values.
Q66458942 is restored.
For some reason, the use on that one Commons talk page did not show up on commons:Special:EntityUsage/Q66458942 when I deleted the item. I verify that an item is not in use at Wikidata (via Special:WhatLinksHere) and not in use in any other project (via "Wikis subscribed to this entity" on "page information" for the item, and then Special:EntityUsage on the corresponding project).
Hmmm.... It wasn't just one Commons talk page (where it wasn't actually included when you deleted it), but more relevantly the structured data of three Commons files (eg c:File:Petra_Al-Kaznah_by_Night.jpg). Not sure why it's not showing up, looks like a bug.
Yeah, phab:T225672 looks related. They better fix this quickly, as otherwise these situations would happen potentially very often these days.
