I agree with not upvoting crap, and I agree that some extra explaining can be useful in many cases.  But several of your examples are just people giving a good straightforward answer where no extra stuff is needed or wanted, and I see absolutely nothing wrong with that.

I don't know about anyone else, but I'm already a super user.  I don't need to be taught why things work the way they do, and I don't need to be taught how to fish.  When I ask a question on SE, it's because I didn't previously know and currently can't find the answer.  All I want is **the answer**.  I'll upvote people who help me get the answer, just like I imagine people upvoted the `cd -` guy because he gave the answer without wasting their time.

I can guarantee you that somebody who thinks installing another OS might slow down his computer doesn't care what virtualization is.  He just doesn't want a slow computer.

Do I think `cd -` deserves so many votes? No.  But it answers the question perfectly, and the next answer has extra details on how to manage more than 2 paths.  All the info you need related to that question is right there.  No one comes away from that page without their problem solved unless it's *a different problem*.  How is that a bad thing?