They’re in a bubble, just like big city Democrats. They really don’t understand how much support Trump has because they don’t personally know anyone who supports Trump (or will admit to it) in the circles they move in.
I’m not sure how they avoid the cognitive dissonance when they see lines around the block to get into Trump rallies, or see that he gets more votes than any Republican in decades, but once you believe something, your brain can explain all sorts of contrary evidence away.
She trashed him in 2016, and Bannon says she left the Administration in 2018 right before the Midterms.