As in Europe, the rising tide of antisemitism on the Left may eventually give American Jews no choice. Just as we see increasing instances of Black groups weeding out anybody they so not want in their supposedly 'public' meetings, we may eventually get to the point where anti-Jewishness on the Left will reach the level where Jews are simply not wanted and not allowed to participate.
This is nothing new. It is just a redux. The hard core Democrats are still segregationists and the KKK heritage they carry with them is still there.
But yes, the article is correct. I have known many Jews first hand who consider the Democrat Party and their Jewishness to be the same thing. It is as if their version of Jewishness is a political party more than it is a 'religion' in the classic sense.
It is also true that some Jews are uncomfortable with Christians and Christianity. Republicans are sold by the media as the White Christian Party, whereas Democrats are portrayed as being modern secularists. This is ironic to me because I consider the Democrat party and Liberalism itself to be a kind of formal religion, complete with dogma and 'faith', but that is a different story.
There is no doubt that more and more Jews are catching on to how most Leftists feel about Jews. How quickly the realization will happen, no one knows.