Imagine if every email and report that you wrote at work was broadcast to the whole world and subject the vicious (yet shallow and unfair) scrutiny of the 24-hour news cycle. Can you see how that would hamper your ability to your job effectively?
Outside of that... not really.
That is part of the job.
Sure, there are crazy people out there. But they're going to be crazy anyway. I think this would make people take the crazy people even less seriously.
[1] https://medium.com/@RonWyden/shaking-my-head-5c1b60db9086#.h...
Also, keep in mind that you won't see emails from a given person which don't match the FOIA search criteria. The likelihood of getting a nonrepresentative sample is therefore proportionally increased.
Do we really want our public servants spending all of their time thinking about whether using "whom" incorrectly will get them crucified by some blogger?
There's also a volume issue.