I think you’re misunderstanding his point. Biden is facing the difficult task of governing a divided country. Trump is looking to consolidate power within his own party. One of these tasks is a historic, perhaps insurmountable challenge, and the other is routine. Even from a completely neutral perspective, this means you will report on more failures by Biden and more successes for Trump.
I personally don’t find this “the media is so mean to Biden!” narrative any more compelling than when Trump was claiming the same thing as president. The media has always been critical of those in power and this is a healthy part of our democratic system.