Josh Barro makes a point pithily:

Both Republicans and Democrats have drawn too strong an inference from Trump’s fairly stable approval numbers during his first term — that Trump has an unshakeable base of nearly half the country that’s with him no matter what he does — but there’s an alternative explanation. Despite all the noise, 2017-2019 was a pretty stable time; 2020 was a year of crisis, but that crisis was caused by an external factor for which voters (reasonably) did not blame Trump; and his administration’s response to that crisis was mostly satisfactory. Then, Trump left office, and he was succeeded by a president who made more economic mistakes than he did. When you frame the record that way, is it surprising that voters decided returning him to the presidency might lead to both more stability and better economic outcomes?

You can quibble with that: I think the public in 2020 formed a negative judgment about how Trump handled Covid, which contributed to his defeat. But I think Barro is mainly correct.

He goes on to argue that the tariffs could change how some of Trump’s soft supporters view him.