As a senior, Hogg experienced the mass shooting at his high school that claimed the lives of 14 students and three staff members on February 14, 2018.
If I remember correctly, Hogg wasn't even in the same building where the shooting took place. The only thing he "experienced" was being in a locked-down classroom for awhile. He was never in any danger. Nobody was shooting at him. He's no more a "survivor" than the customers at the McDonalds adjacent to the campus, or any random motorist who happened to drive past the school while the shooter was shooting.
"I want to go to school and, for lack of a better word, weaponize my knowledge and learn as much as possible to end violence," he said.
I can think of a lot of better words than "weaponize." How about "use," "utilize," "leverage" (if you're into buzz words), "employ," "wield," "apply" ...
It seems to me that a good starting point in eliminating violence might be to eschew the use of violent rhetoric -- like "weaponize."