Student emails. Who doesn't have stories about them? The bad grammar, the terrible manners, the utter lack of punctuation, and, oh yes, the "entitlement." There are plenty of articles on this.
Many of them talk about this as a millennial issue. Millennials have no respect, think everything is about them, disrespect language, etc. But this is not a generational issue.
Let me repeat: this is not a generational issue.
I started collage at the end on the 90's. The internet was alive and...slow. Very slow. Home access was not yet common. Colleges had just started providing students with emails (often their first ever email), but no one really used them. And you know what? Professors still got addressed "Hey!" (in person!), still got complaints about grades, and still got positively terrible papers (oh, yeah, some of those papers were even handwritten. Crazy.)
So why do we see so much of this today? Email is fast, you don't have to drive to campus or look up office hours. And, now professors (and lowly TAs and grad instructors) can keep a record of the rude, obnoxious, and downright uneducated things students send them. I (a millennial, at least technically) have been appalled by students email manners and lack of care regarding their own education. So have my younger (firmly millennial) colleagues. I have also, on unfortunately more than a singular occasion, been appalled by professors' emails. I and most of my (firmly millennial) graduate peers actually tend towards over-formality, for fear of committing these blunders.
So what do we do? We educate. We set guidelines. We instruct. We set good examples. We teach.