I'll wade in since I write often about writing:
I know my "how-to" articles on writing are being read, but I rarely get any comments. I read other writers' articles with a passion, and even I don't comment every time. I'm not sure why. If a writer has blown me away with another way of writing (that "Why didn't I think of that?" moment), I do comment. Perhaps it's because I don't think I need help. Writers can be vain that way (myself included).
And in general, folks don't like to be told what to do or how to do something they already do or think they already do well. (Did that make sense?)
The cynic in me (and he's been growing stronger as I've aged) also believes that some writers don't think they need help at all ... and they're the folks who really should be studying these articles.