Keywords: fireworks vs firework

I submitted the fireworks keyword (plural, as usual for this word) on a movie, but it has been changed to firework (singular). However, https://www.imdb.com/find?s=kw&q=fireworks gives 1258 occurrences for fireworks (plural) and only 216 occurrences for firework (singular). Having both forms makes keyword search more complex. Since it is apparently decided to use the singular now, shouldn't all the fireworks keywords be changed to the singular form?