I’m not sure what you’re arguing. The authors claim that voters hold Biden responsible for a rising cost of living, but they don’t even write the words “cost of living” or “consumer price index” so they obviously are not good at their jobs. In reality, “inflation” doesn’t tell us anything about the impact on the average person. So I think everyone agrees that the authors need to write better. If that’s your complaint, everyone agrees.
But what about Biden? I believe most people believe that centrist Democrats such as Biden are not serious about limiting corporate greed, because the Democrats have consistently failed to address the issue for the past few decades. Bank bailouts, unchecked private health care costs, train staff strike response, the list goes on. If Biden wants to score points with center-left voters, and certainly if he wants to get votes from far-left voters, he’s going to need to pass some legislation to show that the future will be different from the past.
In other words, if he’s all talk and no action, of course people are going to dump on him for it. He’s the president, and he’s certainly capable of doing something. Or you could argue that he’s powerless because of Congress, but then who cares what his image is, because he’s not doing anything, so good for him but the rest of us have other things to do.