After a long hiatus, I made a new account a couple weeks ago because I didn't remember my old account. Minutes after I posted it, I receive 2 "doing it wrong" answers, someone edits my title and tags, and then another person closed in minutes for being a duplicate when it wasn't.
As one of the first people to reach 10k points on SO (I wrote the first SO point guide discussed on Meta) no case could be made that I didn't ask a proper question. I think there are too many people with 10k points now.
Stack Overflow has become a very toxic environment.
In your example, perhaps you didn't know about homebrew and this was going to save you a lot of time, well that's great. There can still be other answers that help your specific issue, but someone has thought outside the box and offered a completely different way of doing it.
For me the value of SO would be greatly reduced if people didn't do that.
However, it is very annoying when I ask a question and the only answers are some variant of, "you are doing it wrong." Multiple times I have had to write an explanation that is longer than my actual question to convince people that I actually do want an answer to the question I asked.
If you really think you understand my problem better than I do, based on a simplified explanation, awesome. I would love to hear a better way to go about what I am doing. But please, try to answer the actual question first (or at least say you don't know the answer). There is a slim chance the "better" way is not actually workable in the real world scenario.
When people ask questions online, far too often the person answering assumes that whoever asked the question must be a complete idiot. There are plenty of topics in which I would consider myself an expert, but I still get treated as if I know nothing about the subject. (I've noticed the problem also manifests itself in academia -- the more prestigious the academic institution, the more everyone assumes everyone else is "incompetent by default").
What irks me is when a google search lands me at SO only to have it marked as a duplicate with no links to the actual duplicate, or when the linked dup is dissimilar or unanswered.
These replies infuriate me. The OP knows what his problem is and he's asking for an answer. He doesn't need a new problem to solve. He doesn't need to know what your opinion is about solving the problem. He needs a solution.
One example: I was searching for how to solve a RVM and rails configuration problem on OS X. I typed the error message from the console into google, and found a SO question that was exactly the problem I was having. But instead of providing an answer, the most upvoted comment was to uninstall everything and use homebrew because "you're doing it wrong" without homebrew.
That's nice and all, but I've had a rails and rvm setup on my laptop for 2 years without homebrew, and, like the OP, I don't have time to set that up now. I just want to fix this one configuration error and get back to work. I quickly went back to Google and found the solution on another rails forum.
Granted, this is a problem with a lot of internet forums, not just SO. But it drives me nuts.