I had previously been under the impression that the photographed reproductions of public domain artwork were copyrighted - further research has made me question whether this is always the case. I wanted to clarify whether the below is indeed an exception, and if so how strong a protection it is.
While searching for public domain images on Wikimedia I found the following: "The official position taken by the Wikimedia Foundation is that 'faithful reproductions of two-dimensional public domain works of art are public domain'." After checking the subsection for the United States, where I live, I found another statement that "Under the rule in Bridgeman Art Library v. Corel Corporation, a mere 'record' photograph of a 2D work of art (i.e. a photograph which is an as-accurate-as-possible copy of the original) acquires no copyright protection."
After reading the article on this case, it seems to be correct that the above is a non-binding but influential precedent, if not law, so long as the reproduction is a "slavish copy" of the original. It's impressive to me that an organization as large as Wikimedia is willing to rely on this ruling, but I also wanted to get an outside opinion.
So, is all the above true, and if so how strong a legal protection is this precedent? Is there anything else I should know about using it?
A secondary question, if the above holds, would be whether this precedent would also allow the use of "slavish copies" that are on websites hosted outside of the United States if I myself live in the U.S.
Bounty Edit: While I'm grateful for the answer I received, I'm making a bounty available for someone who provides a robust and practicable answer directly applicable to the USA. Thanks.