Uh, it's the GOP Senate trying to set up a sham highly partisan non-trial, where the GOP jurors have made their decision in advance and coordinate with the accused/WH on strategy.
Somehow Red and other rigthies have no problem with their side derailing the Constitutional process. Just as Trump's obstruction and non-cooperation with the House didn't bother them at all. The rule of law is for losers ...
Pelosi is trying to get some concessions and ensure that the Senate process is somewhat fair, that Senate Dems have some say and able to call witnesses, etc. It's a longshot with hyper-partisan McConnell in charge, but after a lot of work it's worth making the case to the public and pressuring the more moderate Senate Repubs to allow a real process to play out in the Senate.