C'mon, man! It's all down to optics and narrative with the press. It would look bad for the leftists if their current boogeyman President Trump said something appropriate about the killings and subsequent looting. Not to mention it goes against the narrative that they are projecting of Trump as a wild-eyed, over-zealous buffoon who will kill everybody but his white-bread rich WASP buddies.
I can't even say this is a new occurrence or even an outlier. It's been like this for every Republican President in my lifetime. Nixon was a crook (well, he was), Ford was a blundering boob, Reagan was senile, and the Bushes were both dunderheads. Meanwhile, we had the most honest Democrats like LBJ, Clintoon, and Obama-lama-ding-dong-daddy. Lord have mercy on this country if by some wild chance that Quid Pro Joe wins in November.
Instead of a single tweet with the word shooting in it, parts of Trumps Cape Canaveral Florida speech would be played over and over again if he were a Democrat.