The S&P 500 buyback index was launched November 29, 2012. The first value date was January 21, 1994. From the first value date until one year after launch, the average annual outperformance compared to the S&P 500 was 3.78%. From one year after launch until today there has been no outperformance. The same goes form the value premium. When it was became widely known, it disappeared. That is how markets work.
12.56% 10 YR RETURN Annualized https://www.spglobal.com/spdji/en/indices/strategy/sp-500-buyback-index/#overview