His Twitter banner has an x-ray of his back after a recent surgery, he was 26 so he was no longer under his parents health insurance, and like a quarter of his Goodreads books were talking about chronic pain, back pain, and the medical industry.

Every conspiracy theorist is making it out like this guy is either just a patsy or the Riddler secretly masterminding everything. He's an upper-class outdoorsy kid who got his life permanently fucked by disability and medical debt so he decided to do something about it.

It doesn't take a global conspiracy for an angry young man to shoot an unarmed and unguarded old guy in the street.