About the publicity - criminologists, psychologists, law enforcement, etc. have been saying this for quite a while. The memorials, heart wrenching interviews with survivors and those who lost loved ones, films of the chaos all serve as:
1. Observational learning of how to pull this off. We know these folks study past shootings and fixate on VT and Columbine for instance.
2. Vicarious reinforcement for their psyche. Imaging the outcome lights up your reward systems as the real event does.
So, I hear that President Trump has been informed, Senator Rubio is monitoring the situation (in the Rubio Cave, so what!). What is does say, is that no one gives a crap about me and I'm going to show them. And guess what the President of the USA will know my name, what I did and why! I'm a big deal now.
However, the current media blitz won't change.
As a related issue, the current Chronicle of Higher Education has discussed suicides on campus (not shooter/suicide) and the experts made the point: NO BIG SCHOOL MEMORIALS. Guess why - same idea.