His policies aren’t costing him support anywhere, it’s a common whataboutism that Trump supporters spout to try and claim that Biden is slipping, trying to further erode poll numbers.
100,000 voters in Michigan just voted ‘No Confidence’, because of his policies around Gaza and Israel, or approximately 10% of the vote.
Biden can not afford to lose 10% of the votes he got in 2020. He will lose if he does, and especially not in swing states (like MI).