I think this epidemic starts way before MLB can have any kind of control over it or get ahead of it at all.
Arms, even the strongest ones on the planet, only have so many bullets in them. Pitching is an unnatural movement. When young, children should be focused entirely on building proper arm strength and solid mechanics, instead, children and teenagers are throwing harder than ever, with more breaking pitches than ever. You have little league and high school coaches taking these gifted arms and riding them like mules instead of properly grooming them for the long term.
When you have pitchers who are closer to 10 than 20 throwing in the 80s (or harder) while mixing in power breaking balls, TJ seems less like the exception and more like an inevitability.