I noticed the same issue with keywords related to wildlife taxonomy.  All my essential keywords (common name and scientific classification) which specifically identify a species have been eliminated.  So, for example, a Northern Cardinal (Cardinalis cardinalis) has "Northern Cardinal" and "Cardinalis cardinalis" eliminated.

Same thing for place names, such as the proper names of bridges.

Many of these are the most important keywords (first ones listed) on FT.