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".
Like the paragraph quoted above: it's just so blatantly obvious what's wrong with turns like "considered particularly enlightened", or "there are no underlying principles" that I find it hard to believe that the text as a whole sounds so friendly and convincing, unless you stop and think for a second.
I wish I could write like this about whatever mush is in my head.
It frees me from giving a shit if I'm using e.g. rhetorical tricks in place of good-faith argument. Of course the argument's obviously bad, if you're any good at spotting bad arguments! So are all the others I've seen or heard supporting it. That's why I picked it—it's bad.
I can usually argue positions I disagree with far more persuasively and fluently than ones I agree with, because I'm not concerned with being correct or making it look bad to smart people, nor making myself look dumb for making a bad argument (the entire thing is an exercise in making bad arguments, there's no chance of a good one coming out). Might try that. It's kinda a fun, and/or horrifying, exercise. Drag out those slanted and context-free stats, those you-know-to-be-disproven-or-commonly-misrepesented anecdotes and studies, (mis-)define terms as something obviously bad and proceed to tear them apart in a "surely we can all agree..." way (ahem), overgeneralize the results of that already-shaky maneuver (ahem), misrepresent history in silly ways (ahem), and so on. Just cut loose. No worries about looking foolish because you already think the position's foolish.