If you followed 2016, you remember Bernie's reluctance to drop out and endorse Hillary after losing handily to her in the primaries. He let that all fester straight to the convention and weakened her out the gate. Even after he endorsed her, he refused to talk about her personally, and only went on the campaign trail to talk about his ideas.
I mean, Bernie's not a misogynist, but this isn't the point you want to make to back it up.