I stopped participating in Stack Overflow and Server Fault a number of years ago. Something happened on the way to its popularity, especially on Server Fault. Questions were being asked and a number of highly rated users were closing them down as "not related to SysAdmin". I don't remember the exact nature of the questions, but one that I do remember was related to mobile phones. I argued that the question was valid because a lot of Sys Admins also had to manage phones in their environment.

There was also a general lack of compassion on the part of many, many users. I get that the sites strive to be full of "high quality" content, but there were a lot of legitimate questions asked, in broken English, that got closed immediately, or got closed because it seemed like it as academic exercise they were asking. IT has a reputation for lacking in people skills (deservedly so) and in SO's and SF's early days, that certainly stood out as a major turnoff of the sites. Admittedly, I have no idea if it's gotten any better.