Beef with black feminist types is the main factor. Jesse was used last year as a way to put black men down and made into the ideal black man despite being a biracial man with many of his desirable features coming from his white side. Him moving on to a white woman is viewed as comeuppance and ironic. Serena was viewed as a sex symbol by a majority of black men with white males being the ones who called her masculine. Her moving on to a white man, starting a family with him and black women on social media applauding it is seen as a betrayal.
I don't really feel any way about either besides enjoying the threads