The dems aren't a monolith. They'll come together and close ranks against the left, but they have their own camps. Biden and his camp hate her. Her selection was a totally empty gesture at representational politics. The Biden people don't give a fuck about her career because they will never get a job with her, so they stick her with all this shit. She's never going to be president anyway and no one thinks she will, except maybe her. Even the people who convince her to run so they can make money off her campaign probably don't think she'll win.