Definition of Woke, why the controversy?

As this word is often thrown about on GN as some sort of insult, I thought that perhaps the definition may be useful;

By the mid-20th century," says the Oxford English Dictionary (OED), "woke had been extended figuratively to refer to being 'aware' or 'well informed' in a political or cultural sense."26 Jun 2017

I cannot see why this is used as an insult!