This is incorrect. If the company is public, there is no way to buy stock from a particular set of shareholders without impacting the price of the stock owned

This is incorrect. If the company is public, there is no way to buy stock from a particular set of shareholders without impacting the price of the stock owned by other shareholders. If you own stock in a company that is looking to give money back to shareholders, you definitely want them to do it via buybacks (rather than dividends) for the tax benefit.