I have several friends close to my age who enjoy bashing millennials. I've gotten up and walked away from them when they do because their claims are all the ridiculous ones that so many (particularly right wing) people seem to believe and won't hear anything to the contrary.

Your first suggestion, with the instant gratification, on the surface seems to be exactly what most of these people complain about, the lack of long term thinking. But even as a non-Millennial (by your chart I'm a Gen X'r) I can see why instant gratification is more applicable not just to them but to many of us. The world is changing faster and faster and long term planning can't always keep up. As a child my grandfather would regale me with tales of working his way up from staff driver to Head of Engineering for an area hospital. He worked for the same company for years, had good benefits, job security, etc. He didn't understand when I tried to explain that most of that doesn't exist anymore. Companies are more likely to fire long term employees rather than reward them with a promotion. You simply can't count on any sort of long term planning nowadays. It has nothing to do with "everyone gets a trophy" mentality and everything to do with the reality of rapid change.