For the working class it was high inflation [i.e. their declining standard of living]

For the suburban voters it was the felt sense that we have porous borders and that our tax dollars were being used to support non-citizen [i.e. not getting enough support themselves and feeling the injustice of it]

These are just different misinterpretations of the same underlying problem. What both groups are experiencing is a feeling of economic instability and being left behind while the rich get richer. But Americans have been so heavily propagandized to for decades that we don’t have the political vocabulary to describe the real solution (at least not without using swear words like “s*****ism”), so we grope for some related issue to provide framing. And, of course, very often what we find is some scapegoat the ruling class’ propaganda has ‘helpfully’ provided to us in order to deflect their blame.