A filter cannot be created for Genre or Content Rating if at that moment there are no movies with those values.
Could be please enable custom values to be used for the filter?
There’s already an existing feature suggestion discussing an option to create a smart collection/playlist based on (currently) non-existing values. I suggest you comment/vote in that thread in order to avoid distracting or cannibalizing votes.
Unless I’m missing some unique aspect of your suggestion, I’m going to close this thread as a duplicate.
Voted on that one.
Thanks.
2022 clean-up: duplicate
