It's all the debt. Wages are going to paying interest instead of driving price growth. And as the Fed raises rates, the amount of cash going to pay interest increases in proportion to the outstanding debt, which means a little increase currently goes a long way against inflation. Especially because it's a double effect -- as interest rates increase, money goes from buying things to paying interest, but it also encourages people to take money they would have bought something with and use it to pay down principal to avoid paying the higher interest rates.
This is a good thing in the right amount -- it should encourage a reduction in the total outstanding debt -- but they need to go slow because of the proportionally large effect of a small interest rate hike against the unusually large amount of existing debt.