I don't think that guilt, shame and self-hatred form a particularly sound basis for progressive politics, is the thing. (Someone posted something about this here a few months ago which was quite good on this, I'll see if I can find it - Fisher wrote about it in his 'Vampire's Castle' piece, too.) You're never going to win a popularity contest by telling people they're revolting and shameful, and for better or worse, democracy is a popularity contest. At any rate, it should be no surprise if many people are more inclined to follow someone who seems to be saying something positive about their culture, which unfortunately comes along with a whitewashing of past injustices or a desire to roll back some of the progress that has been made since then. I don't think it's unreasonable that people are going to say to themselves "Why should I support people who say they want to kill me, when they quite clearly don't want my support in the first place?". If we interpret #KillAllWhites to mean simply "fuck off whitey", then it seems like a good idea for white people to do exactly that, rather than insisting on foisting their 'solidarity' on people who very clearly don't want their solidarity or anything to do with them. And the phrase can clearly be interpreted rather more literally, seeing as there have been racially motivated attacks on, and murders of, white people by black people just very recently (contra your cute comment about 'delicate souls getting scared').
In fact you sound like you're saying the cure for racism is for black people to harass, beat and shoot white people until whites simply agree not to be racist any more. Which sounds about as likely as Islamist terrorism eventually defeating Islamophobia.
The suffragettes used disruptive tactics in support of demands for a specific privilege - a privilege men already had - which they eventually achieved. Ditto the civil rights campaigners of the 1960s. They weren't just spewing random hate in all directions. I appreciate that most race and gender activists don't do that, obviously, but inevitably it's the ones who do that get the most attention.