It’s not new, buybacks have been increasing for decades.

A bonus 1% tax on buybacks was recently added by the Inflation Reduction Act, and Biden has called for that to be increased to 4%. If the tax is high enough, more companies will go back to paying dividends.

They were legalized in 1982, so no, definitely not new. Simply put, it took norms and customs awhile to develop around using them, plus the Net Investment Tax came into effect making the tax savings more substantial.