This is just plain wrong: "The reason school shootings happen is not because of poor gun regulation, or poor access to good mental health care. That’s crazy."
Also wrong: "There is a 52-page profile of school shooters written by the FBI. That profile should be one sentence: “School shooters hate school.”"
And then the simplistic and wrong conclusion: "No, school shooters pick schools. So this should be an easy problem to fix."
The reason why the FBI has a 52-page profile of school shooters is because it's a complicated subject.
As a general rule, whenever someone offers an easy solution to a problem that has plagued society for a long time, do not trust them. And if you are the one who came up with that solution, consider that you've missed some important facts and probably shouldn't be armchair diagnosing.