Buybacks and dividends are financially equivalent. They give money from the company to shareholders. The incentives are exactly the same for all parties involved, too.

Their only material difference is in taxes. Yes, I am in favour of putting dividends and buy backs on the same tax footing, just in the name of simplicity. And while you are at it, also put dividends and interest payments on the same tax footing.

At the moment, many jurisdictions advantage interest payments, thus encourage financing companies with debt instead of equity. And then they awkwardly pair it with other rules that try to tell companies (especially financial companies like banks) not to use so much debt, not to be so levered.