Maybe the article is wrong, or did you just not see the preamble?
Here’s a highly abridged list: https://www.insider.com/british-empire-stole-cultural-artifa...
The owners have asked for them back and been refused. I don’t see that as a historic issue, I see it as a current one.
When directly asked to return items they say no.
https://www.britishmuseum.org/about-us/british-museum-story/...
What’s hard to hate about that?