For understanding the intent of people currently reddit is the best. Back in the days facebook groups and comments on the posts used to tell what people were having issues with, what are their pain points. But now a days facebook posts and comments are all filled with nothing useful but memes.
So yeah getting behind the real pain points of audience, reddit comment works really well.
Few days ago i myself was searching for something and reddit comments helped.
Although it doesn't replaces tradition keyword research but surely one of the best helpful tool now a days.