I don't think follow 4 follow actually works very well. People are just trying it because they are trying every angle to succeed. Some of those strategies are actually detrimental but it's not always clear to see at the outset.

I don't think Steem will be dominated by 'follow 4 follow', but there will always be an element of people commenting relatively superficially in the hopes of gaining some attention. I don't think that's a huge problem, certainly better than the state of other platforms where there is no incentive to be pro-social at all.