I'm happy to not be seeing much hate speech on Steem, yet. That could change if/when it grows to millions of users and becomes a more attractive platform generally. One issue with flagging is that there is little financial incentive to do it, but people will happily vote up any old crap if they think it will make them money. I do flag stuff, but it's mostly what I see as abuse of the platform for profit. I don't flag stuff I just disagree with. If I see something that really is spreading hate then I will consider flagging that. Of course a lot of people are wary of getting into a flagging war with others who have more power.
I want to see Steem grow massively, but I hope that it does not get overrun with those who seek to sow hate.