Why don't you an active member of Server Fault bother to vote on people's answers1?
I guess itsit's this:
I usually only view questions iI personally care about, which by the time iI wade through all the stuff that's not a favorite tag but shown to me anyway isn't too many. At this point i'mI'm already pretty disengaged.
I usually care about questions which iI find interesting also.
I usually find them interesting because iI don't know the answer myself.
Which means iI can't really upvote the answer as iI don't know that it's correct.
Sometimes i'llI'll enter questions iI know the answer to and upvote the correct answer or drop an answer myself if nooneno one else has, but only really when iI actively decide to do a spell on SF. The majority of the 3-4 times a day iI drop by i'mI'm looking for interesting questions on lunch break, or before / after hours. In those instances the non-favorite tagged questions just obscure anything iI cared about in the first place. I believe there's a specific url you can use to filter that stuff out, but that's roughly about the point iI stop caring and just go onward to the next website.
I guess that personally SF is a place I primarily come to for learning. Answering and helping people is a nice side effect, but the main reason i'mI'm here is to see the answers to things iI didn't already know and try and gain knowledge. That gravitates me towards answers iI can't actually upvote.