In his eyes, Bernie Sanders was the only candidate who gave a fuck about guys like him. "No one is willing to help me," he said, and broke down in tears as he pulled a picture of a squirrel out of his pocket. He sobbed and explained that hunting squirrels and other small animals was how he kept his children from starving when the food stamps ran out for the month. Now, the good news is that most Americans have seen their economic prospects improve over the last eight years, but that's zero fucking comfort to a guy who has to hunt squirrels to keep his children fed.
And it's also sort of the point. A lot of the Bernie or Bust people are your traditional Bernie Bros. But many, many more of them are voters who, for the first time, see a candidate who is speaking to their issues, and giving that up would be like throwing away a life preserver. Even if they've now washed ashore, and it's preventing them from escaping a tiger that's coming after them.
We've seen this story play out before in a wealthy, well-educated country. You already know the example I'm going to use, and you're going to groan. Hear me out, this isn't a "Trump is literally Hitler!" thing.