Regardless, stock buybacks were once considered illegal in the United States because they were viewed as a form of stock market manipulation.

The core idea behind this concern is that buybacks can artificially inflate a company's stock price, which might mislead investors about the true value of the company.

https://www.forbes.com/sites/aalsin/2017/02/28/shareholders-should-be-required-to-vote-on-stock-buybacks/?sh=7f56517e6b1e