Essentially there’s 6 frames every second that need to be dropped or processed to get down to cinematic 24frames. Though if it’s played back on broadcast tv it’s back at 30. There are endless debates on wether this is worth it or not on the internet. It really comes down to what details you want preserved. Google the hobbit 48fps for some interesting arguments on it, Peter Jackson was the first to really experiment with high frame rates and the results were not as some expected.Forgive my lack of knowledge, for I am a stills only guy, but why is 24p so important? What’s wrong with using a different frame rate?
Edit: I should have said the internet along with every director, critic and film room editor. FPS arguments have a lot in common with right vs left, nature vs nurture, free will vs destiny, etc. it’s a matter of choice for some that borders on fanatical.