By contrast, Biden at the same point in his term was hovering around 39%, for the heinous crime of... rebuilding the US economy? Including some woke riders in his infrastructure bill?

At this point, a fair assessment of US citizens is that on average, they seem to consider that being a right-wing autocrat wannabe, threatening to invade allied countries "as a negotiating tactic", being a climate change denier, starting a humiliating failed war, trying to blackmail the press into compliance, etc, are about 3% worse than being a cringe center-left bureaucrat.

"US citizens don't seem to care" is an apt hyperbole.