To understand much of our language, Gnorts would have to already be aware that our words and symbols gain meaning from how they're used, and you couldn't, for instance, determine that a swastika is offensive (in the west) by its shape alone.
In this case, the term "colored people" gained racist connotations from its history of being used for discrimination and segregation - and avoiding it for that reason is the primary principle at play. There's also the secondary/less universal principle of preferring "person-first language".
Switching to another word isn't ceding power to the bad people. It's taking away their power to redefine things. It's letting them have the now-useless word exclusively, which will become associated with their speech, and not the original meaning. The original meaning is reclaimed by using a new not-yet-soiled word for it, and the cycle continues.
* had everyone declare their pronouns
* advertised their segregated black-only event next month
* repeatedly interrupted to chant "trans rights!"
This is a very common cluster of behavior, and I'm not sure what I would call it other than "woke". If there's another word that would be better, I'm all ears. But my experience has been that proponents don't find any word acceptable, because what they object to is the very idea that this is a distinct cluster of behavior. They feel, as the source article says, that each of my bullet points is just an independent matter of respect.