The billions that were printed? That hasn't had anything to do with it.
The major central banks dont print legal tender. So there is a reason it has nothing to do with it. US Dollars are created when the commercial banking system makes loans, not when the Fed prints their reserves which are bank instruments.
Of the 320 million Americans, not one single individual even owned what the Fed "prints". Hence it is impossible for the Fed's "printing" to lead to higher prices.
RE: Who is responsible for inflation?