Academic research going back "many" decades have generally reached a different conclusion. Ten years is actually a relatively short period to reach definitive conclusions. And, of course, this has been a roaring bull market where, historically, low-vol strategies have, indeed, trailed the performance of high-vol strategies.

It is well known that the tracking error of most low-vol strategies is very high. (A few years ago, actual low-vol portfolio returns vs. risk were looking stellar.)

That said, it is a bit concerning when an anomaly gets well-known and then is put into practice it often seems to fade away. Recall the "value effect" and the "small-cap effect." Both go in and out of favor - often over very long periods of time. All in all, very humbling!