Another way of seeing it is "nobody is".

I can decide what brings value to ME. But I shouldn't judge on behalf of THE COMMUNITY, nobody placed any power-of-attorney in me ! I can only talk for myself. You can only talk for yourself, you cannot suddenly decide that, because YOUR PERSONAL JUDGEMENT says that it doesn't bring value to you then it automatically means that it doesn't bring value to THE COMMUNITY.

Actually, I'm not sure you even realize the enormity of what you've written ... We get to vote FOR OURSELVES. Your vote indicate what is valuable (or not) FOR YOU! You have absolutely NO RIGHT to imagine that you speak on behalf of THE COMMUNITY.

YOU and THE COMMUNITY are distinct entities. THE COMMUNITY as a whole cannot vote. What is valuable for it results from the aggregate of individual values. If you flag something that many people upvoted it means you are challenging the judgement of the people who upvoted, you are defying them, by annihilating the effect of their vote you want to deny them the right to express their appreciation. It is extremely destructive.

In case the value comes from bots then it means you are defying and challenging the current steemit system. You can do that indeed, I too believe the current HF19 could do with some tweaking, but I think downvoting is the wrong approach. We should instead plead with whoever can do something about it to change the system.