Is this stuff just not taught anymore or is there a sense of entitlement these days that paying for training, a type-rating or worse affords these individuals?
Please don't tar us all with the same brush. I'm a relatively new FO and must admit to being very proud to put on the uniform and wear it properly, top buttons and all. Conversely, one of my training Captain's rarely wore his tie and jacket because "why should I start my duty hot and sweaty?".
With regards to Instagram (and other social media), I don't have a problem with people sharing photos/videos for others to see what goes on behind the cockpit door, and some of the unique views that we're lucky enough to see. I think there's still an element of mystery/awe when it comes to airline flying that the general public find interesting. For example, I used to watch Just Planes "from the cockpit" videos as a kid and it really fed my desire to pursue the career.
However, I think that using the cockpit and your uniform to take selfies for your own gratification and mainstream media attention is a slippery slope, and takes it a step too far.