Fewer people know Latin in Britain now. So the Latin derived words are usually used as fully adopted words target than being treated as quoted Latin. This seems right to me.

"Forums" (rather than fora) seems a little awkward to me, but "data point" seems more natural than "datum". But then I never learnt Latin at school. At some point we need to stop applying the grammar rules of foreign languages to fully adopted words.

the point is that they were initially adopted specifically in this way in the dictionary in the first place. Ignorance and years of bad education took their toll.