As others have mentioned, the term has its origins in African American English, basically meaning “stay aware of the systemic forces that oppress us.” According to another user here, apparently this word was in use since the 1930s.

However, I never heard it until about 15 years ago or so, when I started noticing it filtering in on the more left wing spaces on reddit. Initally, I was mostly confused by why anyone would mangle english so much - but through more exposure, I realized that the word wasn’t being used to communicate information, so much as signal cultural affiliation. And the word’s transition from use in black american culture to reddit, where I found it, became obvious. Like so many other things in black culture, it had been coopted by white people - in this case, 14 year old Tumblr feminists.

Bill Burr has a great bit on this change, where he points out that “woke”, in its traditional black usage, sounds very cool. But, coopted by white people, immediately becomes uncool. And it’s uncool not because of the word itself, but because of the people who use it - white people trying to boost their social capital among their peers by demonstrating their familiarity with black culture. And thus, the term takes on a negative connotation - the connotation of “ugh, fuck, here we go - another lecture.”

In pockets of liberal/left wing culture, “woke” may retain its original meaning to those who use it. But among the vast majority of the population, self-describing as “woke” is cringy. It is basically outing yourself as being terminally online, basing your self esteem on how much of a good person other people think you are, and feeling holier-than-thou.

Hence, conservatives identified a natural slur against their enemies, and started tossing it around as much as possible. This works for them because, even if their takes are as dumb as possible (and lord knows they try), no one wants to defend “woke people”, because woke people are cringe.