As a writer you want to convey your ideas, thoughts or realizations. Some just like to share, some would like to make life easier, by analysis and understanding more deeply; some need an outlet for their pain.
What it also means, is this:
Sharing thoughts, ideas, movies or results of research does not mirror one’s own experience 1:1 in every single case.
Humans are capable of a wonderful gift: Empathy.
That is what sharing can be about:
Empathising, because you feel or hear the others’ pain. And for those that feel pain the fact that someone actually understands can be a wonderful relief.