Hoi,
Thank you for the overly broad misrepresentation. As always, copyright is predatory. As we can prove that copyright is the enemy of science and knowledge we should not be upset that copyright is abused we should welcome it as it proves the point. Also when we use texts from everywhere and rephrase it in Wikipedia articles "we" are not lily white either.
In "them old days" generally we felt that when people would use Wikipedia, it would only serve our purpose; share the sum of all knowledge. I still feel really good about that. And, it has been shown that what we do; maintain / curate / update that data that it is not easily given to do as well as "we" do it.
When we are to be more precise with our copyright, there are a few things we could do to make copyright more transparent. When data is to be uploaded (Commons / Wikipedia or Wikidata) we should use a user that is OWNED and operated by the copyright holder. The operation may be by proxy and as a consequence there is no longer a question about copyright as the copyright holder can do as we wants. This makes any future noises just that, annoying.
As to copyright on Wikidata, when you consider copyright using data from Wikipedia. The question is: "What Wikipedia" I have copied a lot of data from several Wikipedias and believe me, from a quality point of view there is much to be gained by using Wikidata as an instrument for good because it is really strong in identifying friends and false friends. It is superior as a tool for disambiguation.
About the copyright on data, the overriding question with data is: do you copy data wholesale in Wikidata. That is what a database copyright is about. As I wrote on my blog [1], the best data to include is data that is corroborated by the fact that it is present in multiple sources. This negates the notion of a single source, it also underscores that much of the data everywhere is replicated a lot. It also underscores, again, the notion that data that is only present in single sources is what needs attention. It needs tender loving care, it needs other sources to establish credentials. That is in its own right what makes any claim of copyright moot. It is in this process that it becomes a "creative" process negating the copyright held on databases.
I welcome the attention that is given to copyright in Wikidata. However our attention to copyright is predatory in two ways. It is how can we get around existing copyright and how can we protect our own. As argued, Wikidata shines when it is used for what it is intended to be; the place that brings data, of Wikipedias first and elsewhere second, together to be used as a repository of quality, open and linked data.
Thanks,
GerardM