It's a logicial fallacy to assume that just because there are more operations today the problem is getting worse.
Except for the fact that Dr. Andrews himself says the problem is getting worse.
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There is nothing kinetically wrong with throwing a curveball, as proven time and time again by medical research. I would be wary to teach a young pitcher to throw breaking pitches, however, because lesser-developed bodies struggle repeating mechanics when fatigued. When a pitcher begins compensating for a lack of "stuff" (for lack of a better term) by altering his mechanics, that's when things can go wrong. Young pitchers don't know how to properly cope with the necessary adjustments on the mound, and that is why the principle of breaking pitches being bad for the arm has been developed.
This. A properly thrown curveball isn't a problem for pitcher at any age. The problem is that many kids either don't learn to throw a curve properly or they rely on it so much that they develop injury problems due to fatigue.