Perhaps if you enlighten them, you'd help people make more informed decisions. And maybe they'd care about the problems. As it is, smugly chuckling at ignorance is rather silly. If they don't know, it isn't irony.
I guess the irony is that they "ought to know", given that OP associates "leftism" and hipsterism (social warriority?) with rudimentary eagerness to be up to date on current "issues".
Ignorance does seem to be the willful plight of the further-leaning left at the moment, so I have to somewhat agree with him. But I get your point.
Willful ignorance is endemic in America these days. I'm rather curious what specifically the further left-leaning segment of the population is willfully ignorant of at the moment. Care to share?