These approval numbers from Morning Consult are historically terrible and show Biden above water in roughly the same patch of territory Carter and Dukakis managed to win in 80’ and 88’ respectively. I suspect Biden could clawback support by Election Day 24’ in some of these places, but not enough to win an electoral college majority unless he really starts shaking things up.
My fear now is you get a smarter Trump like DeSantis to pick up the MAGA mantle and fuse it to a more mainstream Republican alternative to Biden. If the race becomes a referendum on four more years of Biden rather than another Trump term, Biden is in real trouble. With Harris underwater even more, there is really no alternative standard bearer we could muster in time for 2024.