Two reasons....
1. The killer lived. The swine will be a constant nagging reminder every time there is even the tiniest update to his status and the pending court case.
2. The massive failure of everything that liberal progressives hold dear. They demand you place all security trust in the state...it failed at every level, from Sheriff to FBI to School Administrators to Social Services. George Soros will be glad to spend billions of dollars to shield ALL of what they revere from accountability to the fake outrage and targeting of the NRA will be endless as noise to distract.
Don’t forget that the victims were all white. The same number of black kids are slaughtered in Chicago each and every month. But they’re far less newsworthy.
You missed one (the most important one):
175K New RAT voters from Puerto Rico