Thinking about the President's reaction to this, a few things come to mind:
1) If your moral compass is as skewed as the President's is, you're not going to see (and blind yourself to) the wrong that KR did
2) He cannot afford, as this stage in the election cycle, to alienate people of KR's ilk; they are a key part of his base
3) Charlottesville Part 2 - more "very fine people"?
4) Rule 1 of "How to be President": unite, don't divide (he's passed that turn a few blocks back).
Slightly o/t but this to me remains, to date, the most hypocritical feature about the current American right and in particular the Trump campaign and subsequent presidency:
Their incessant and ubiquitous whining about how the left has descended into "identity politics" while they have completely and utterly entrenched themselves in such identity politics themselves - except to them it's not identity politics because the identity they're serving is a very narrowly defined set of backwards, xenophobic middle-aged and above white people holding racial resentments that American Presidents have tried to address since the 70s.
Every single president after integration has made some sort of effort to reach across the aisle or at least address all/most Americans regardless of party affiliation.
The only one who hasn't, and has been playing a race/gender/age/region/sexuality-card ever since his campaign announcement speech, is Trump. And it's only gone downhill from there - in no speech ever has he tried to paint democrats or people living by the coasts or immigrants as even human, let alone patriotic Americans who he wants to serve during his tenure. Never. That is the definition of identity politics.
But it goes to show how deeply ingrained racism remains in American culture when being a white male is seen as the default to the extent that nobody is willing to call a spade a spade when a president engages in vicious identity politicking for that one default demographic.