Because the Alt Left, wrongly claiming to be “Liberals” has made a cult of victimhood. The bigger victim you are the more “heroic” you are to the Alt Leftists. So they create an imaginary world for themselves to achieve victimhood.
That why the Alt Left is so hysteric about Trump. People who been lied to by their political masters for decades about their victim status never get mad at the liars, instead they go ballistic on the one forcing them to confront the truth.