Films not added to "Baseball" interest group?

From what I've seen elsewhere, it seems like if you add "baseball-sport" as a subgenre on a listing, IMDb will add that listing to the appropriate "Related Interests" group: https://www.imdb.com/interest/in0000167/?ref_=tt_rin_in_i_2

But for a couple of recent entries, I haven't seen that happen. Is this a bug?