L-1) There's a purely informational layer, where he's talking about the meaning and history of the phrase "cargo cult."
L-2) There's an logical layer, where he attempts to use the information presented to persuade the reader to (not) modify their beliefs, feelings, or actions in some way.
L-3) There's an attitude layer, which involves the way he addresses the reader, his "virtue signaling," the quality of his writing, his overall tone.
(In another situation I might also consider:
L-4) The presentation layer, which involves the look of the website, its responsiveness, etc.)
In my opinion generally information should be most important, and then we look at the logic, and last but least consider the attitude. But I feel like increasingly in society we look at the attitude and if it turns us off, we summarily discard the entire thing, or even take an opposing view on principle. Even if the information and logic is sound. Hence the bulk of the comments here dismissing what he's saying out of hand because essentially it's too woke.
So my answer is that even conceding that the things you mention ("preachy" "holier-than-thou" etc.) are negative, ideally we ought to be able to critique just that layer without discarding the rest of the communication.
EDIT: Responding to your edit, I think he has no more or less right to decide what's good or bad than anyone else. Just because he's saying we ought to reject the phrase doesn't mean we have to actually do it, so I don't feel personally offended or enraged by his exhortation.
So, it makes sense that the thing the author prioritizes and focuses on will be criticized. Would many be criticizing a historical article on the origins of the term, or the plights of the people it covers?
Collective consensus.
But that doesn't mean the author is not entitled to have an opinion and express it.
The commenters who dislike the general tone are of course entitled to express that, however, it is baffling to me that the argument is that Author is entitled to their opinion and the commenters who disagree should not comment.
>> And who gets to decide what's "bad behavior" >Collective consensus.
I know this is generally the way of things however, I dislike this as it is mob rule.
Depends. Have you heard of the terms or phrases "preachy"? "Holier-than-thou"? "Pearl-clutching"? "Making mountains out of molehills"? "Language police"? "White knighting"? "Misapplied effort"? "Professionally offended"?
Are those positive?
And who gets to decide what's "bad behavior" and what's merely use of an old term? Based on what? Their feelings that use of the term offends someone from some group that they themselves don't belong to and have probably never even talked to IRL? That it's use implies some intend? That certain practices of some groups can't be referenced as a name, if those groups have had a sorry past? That the only ethnic people who use such terms are just the ex-opressors of said group, and not also people who have been themselves colonized or opressed? Does he think e.g. Jewish or Latin American or African developers don't use such terms too to describe the notion?