Well, fruit picking up the users is not cannon as of now.
We know for a fact that 200 years ago someone had Nika df but not in awakened form.
So, one can simply argue that fruit passed down since 800 years ago and was eaten by others like any other fruit if old user dies.
However, with Luffy two things changes this narration to some extent if not certainly.
1) Zoans dfs have will of their own
2)in wano we learnt that prophecy was that a certain point in future someone will appear to save them and momo was sent into the future at that exact moment.
This kind of implies Luffy was destined to be joyboy and was destined to eat Nika Nika no mi.