This movement to rethink our monuments has a lot to do with our information age.  We have a lot more information about historical figures than ever before.  All their virtues and sins are now exposed to the world.  

When I was a child, we got our information from textbooks and newspapers and perhaps a biography from the library now and then.  It turns out that all those sources were sanitized or the writers didn't have full knowledge about their subjects.  For example most people had heard that Thomas Jefferson owned slaves but there are a lot of other interesting narratives that were not general knowledge.

Personally, I favour change over clinging to an idea of the past that was a bit of a facade anyway.  Those folks are gone now, dead and buried. Let's not condemn them; they were products of their time.  But let's move on and make our public spaces welcoming for the people living right now.