I have said all along that the increased government spending and debt is inflationary (which is why I predicted short-term inflation around 5%), but, theoretically, it is definitely possible for increased government spending to lower inflation. It depends what is causing the inflation and what the spending is used for. And by inflation, I mean the word as it is used in the modern world by economists and educated people everywhere, not your preferred definition from the Dark Ages of economics.
I'm sorry, but I am not aware of what Biden actually said or what his rationale was for saying it, so I can't comment on those specifics. As you know, I am a strictly objective facts and logic person. Without all the prerequisite relevant facts, I can't possibly apply my superior logic skills to the question at hand.