Well, I think it's a fair question asking how the person died, but timing and the way the question is posed might seem unreasonable to the family of the deceased.
I like to know the cause of death to warn others to avoid certain lifestyles. So it's a fair question, but others might think differently.
Yes, those are good points. In this case it was social media, so you can never really know the tone of the post.
That's right. Informations are interpreted differently on social media.