In interviews he's given it really seemed like it was his choice. He obviously rehabbed it to the point where it was strong enough to win an NCAA title. Carson Kharchla did the same thing. Personally, if it was me, I would just repair it and get it out of the way, but I can't pretend like I'm an expert or know what's best. I'm assuming these athletes, their families, and coaches have done their due diligence before deciding whether or not to surgically repair their torn ACLs.