How is their ignorance of historical fact symptomatic of a desire to blame other people for their problems? You and the article are conflating normal stupidity with snowflakery and the two don't necessarily go together.
As for the frozen crystalline precipitation issue, I think its more a case that an increasing number of people are aware that they have 'rights' but miss the point that in addition to those rights, they have responsibilities, and that other people also have rights. This is compounded by the fact that people seem to enjoy finding offence, both on their own and other people's behalves, in just about everything, even when there isn't any offence intended. The issue is then exacerbated by people lacking compassion and assuming that anyone who makes any kind of complaint, legitimate or otherwise, is simply whining for whining's sake.