Good points. Flagging a post should only be used for inappropriate content like porn, viruses, spam or phishing attacks. Not if you disagree with the author.
On other social networks people will mostly not vote for a post if they disagree on it. Unpopular viewpoints will never rank high. That's how it works and I see no problem with that. As long as other viewpoints can be shared without them being flagged down.
Question for Steem is: Are people upvoting because they like the post or are they upvoting because they think others will upvote. Let's be honest. Most people here are voting for the money so they only upvote the viewpoint of the mass. Even if they disagree themself. I think that's a problem.
I agree with that last statement, I Upvote posts because it's stuff I like to read about, or because it's a somebody I know is going to garner a lot of votes. Get on the bandwagon. But it still requires me to learn about that subject, because if you can get a good reply out and start interaction, you can reap even more benefits. So it's probably good to do both.
I agree there should be some countermeasures for malicious content such as viruses, spam or phishing attacks. However what consists of inappropriate content is entirely subjective and that is the problem. They're should be a place for everyone. However, I would not be against a "clean" front-end for steemit that moderates "offensive" content. I just don't think the flagging should be baked into the block-chain. This is antithetical to steemits claim of free speech protection.