It's an unprovable hypothesis since it requires two alternate histories to compare and contrast, and how do you weigh short term vs. long term outcomes? How do you compare increased harm on one group with reduced harm on another group? For example, what if one candidate will increase homophobia while another one will start more islamophobic wars. Which am I supposed to support? It's just vibes based ideology. By attaching themselves to Democrats (by advocating for voting for them) they discredit themselves and make themselves bourgeois collaborators and reformists.