Even with the plethora of information available, there are times when a writer needs to seek advice. Maybe s/he has a scene and wants to make sure it's realistic. Or maybe s/he's looking for information about a little-known 15th century serial killer. Whatever the reason, the author may post the question on various writing-related loops. After all, there's a good chance someone knows the answer. Right?
Depends. While there are people who are helpful, there are those who seem interested only in touting their opinion. Worse, they become upset when people don't follow their advice. Some even venture to try to rewrite the author's story without even knowing all the details.
If you're one of these people who do the latter, stop. Please. The story is not yours. Unless you're the editor, a beta reader, or critique partner, it's not your place to tell the author how to write and/or revise his or her story. Even if you fervently believe you're right, you may not have all the facts necessary to make a decision.
Most of us want to be appreciated and acknowledged. Sharing advice is certainly one way we can accomplish this. It feels good when someone mentions how our advice has helped him or her.
Perhaps it's a good idea to remember YMMV.
Your mileage may vary. :-)