Yep, yep, yep, I hear you loud and clear. I am relatively new here and just last night I was learning more about the flagging system and this is the exact same thought I had. Community censorship as you refer to it will certainly need a very nuanced and elegant algorithm to kill the clear cut bullshit, but leave the regular ol bullshit (ie: that other asshole's opinion...hhahhha)
Generally speaking, I'm just not comfortable with the idea of prohibition of ideas as I'd like to think (in a perfect world of course) that the most meritorious ideas will float like cream (I realize this is a very naive stance). We'll see, but the point you are making is critical.