The reason is more technical than that. For a long time the Fed has had a target of 2% PCE inflation (which is a bit higher than 2% CPI inflation), but in the past decade it’s averaged 1.5% or so. This damages central bank credibility, a very important asset for monetary policy. Thus, policymakers are comfortable running 3% or so PCE inflation for a while to try and bring up the long run average to the 2% stated target.