First, the polls:

https://www.realclearpolitics.com/epolls/2020/president/us/2020_democratic_presidential_nomination-6730.html

Next, the reasons:

  1. Joe Biden was the primary creator of the "Dear Colleague" letter campus sexual assault kangaroo courts that blatantly infringed on the due process rights of the accused (primarily men): https://www.politico.com/magazine/story/2019/04/03/joe-biden-college-campus-sexual-assault-226481

  2. Joe Biden called men cowards if they see a woman suffering violence but don't do something about it, i.e. men must protect women at their own risk even though it would be victim blaming to say the woman has any obligations (listen very carefully): https://www.youtube.com/watch?v=Hjvncps88C4

  3. Joe Biden yelled at men and shamed them to "do something" about violence against women with a vulgar and highly unnecessary reference to the rape scene in the movie Deliverance (again, it would be victim blaming to say the woman has any obligations): https://www.youtube.com/watch?v=XDxTChzikqI

  4. Joe Biden engages in creepy behavior around women that would hurt other male politicians in the #MeToo era, but he gets a free pass from #MeToo since he helped create the anti-male environment that allows them to flourish: https://www.youtube.com/watch?v=ZAymXlGSplU

  5. Joe Biden was the creator of the Violence Against Women Act which in its original form, patently denied domestic violence funding for men (full coverage for men still has not been implemented): https://en.m.wikipedia.org/wiki/Violence_Against_Women_Act#Coverage_of_male_victims

Finally, the takeaway:

Joe Biden has a history of throwing other men under the bus. I don't know why he does it (but I have my theories). I just know that he is an enemy of the men's rights movement, and I have presented here the facts to prove it.