The greater the number of participants, the lower the quality of their participationthe average participant. That's just the law of averages at work. I rarely participate here anymore, because I can't get help for my problems. There comes a point where fake Internet points isn't enough to keep someone around.
I think that many of the most upset people should have stopped participating in Server Fault long ago as part of the normal attrition rate of a community like this, but instead are hanging on to the way things were 5 years ago when there were a small fraction of the page views that there are now. That doesn't help anyone. If you are truly upset at what the community has beginbecome and you haven't been able to figure out how to fix it in years then maybe there isn't anything to fix. Maybe that's just how things are now and you should try to accept it.
As an "outsider" now, it seems silly to see people debating the merits of the words "professional" or "off topic." The people on this site that truly care about that type of thing are statistically irrelevant when compared to total page views. So, I see two options:
Reduce the barriers to entry. This will likely drive away a few more top users (who maybe should already be gone), but will make it a more welcoming place to random googlers.
Greatly increase the barriers to entry by having some type orof new user approval process. I don't think that this is realistic, as private communities are not part of Stack Exchange's mission.
I think #1 aligns with Shane's suggestion.