Occurred to me that this must be a phenomenon after reading synopses of The Fire Within (2022) and Fire of Love (2022)--- currently omitted from the article. One gets the sense that it is more common than it ought to be, but the question is why? Birthday problem helps to prime the intuition that it's maybe not that unusual to have some matches of "topic" but the extent to which the listed examples are similar (in multiple respects simultaneously) requires more explanation.
See also: Antz (DreamWorks) vs A Bug's Life (Disney/Pixar), both 1998