I likely fall into the kindness over niceness camp to the detriment of certain "social etiquettes" at times.
I like the first article. My thoughts come in two parts.
First, that it articulates certain things I think about certain forms of "niceness" and social etiquette; it's letting the room do the thinking for you, to let them decide for you. It's thinking about everyone first at your own detriment, since it at times removes you in entirely from the equation. To be wronged and then be socially pressured into smiling about it is a double slap in the face. Why must I be gracious for your mistakes?
Second, I think that a lot of these forms of social etiquette favour and shield the true transgressor, which is something I have a problem with. Many would sooner skirt over the real troublemaker so as to not be subject to the 'ugly' view of someone getting angry and/or cutting off the withering branches of the social group once and for all, instead letting it fester.
I appreciate the article highlighting that simply choosing to be "nice" isn't necessarily kind. The fact that one is not socially expected to "talk back", "rock the boat", and to just let the transgressor be in peace is simply socially-conditioned, socially-enabled silencing. The transgressor often knows this, and cowardly hides behind the wall of people who would defend them because you, being the one to speak out, aren't "being nice". "You know how he is!" "Just let it slide," etc. It is many layers of wrong and I get the sense that not many see it.
I must admit that my first intentions first and foremost are not necessarily even to be "kind". It simply is that doing the "nice" thing is the plain wrong thing to do, period- and I do not mean that necessarily morally either (referring to my first point above). My follow-up actions being "kind" would be coincidence. To explain further; someone initiating these social exchanges are forcibly pulling you into their game, their dynamics, where you would then be expected by both them and the room to continue playing in a certain way. It is covert social coercion, something I despise. Nuh-uh. Morals or not, I despise that and would not stand for it. Bring your own pawns.
The article says this:
"Being kind doesn’t always mean being nice, however — because the truly kind response won’t always be pleasing to the other person."
You have a choice. You be nice, and please the transgressor, the wrongdoer and everyone else who enables it with their silence, sitting in what is ultimately silent approval, OR, you stand up and offend everyone but the victim.
You're afraid of offending a whole room? You feel that offending 10 people is worse than offending just one?
The quantity doesn't matter here. Guilty is guilty.
To offend the room is to offend them all individually. They will pile in on each other and agree that you're being a pest. The transgressor will laud them for being the perfect pawns they were, simple extensions of his twisted will, feeding into them and encouraging their toxic growth. Point being- they have each other.
What about the victim? In a room of 12 people (transgressor, you, 10 other people) only one defended them. They only have one person.
"Keep the peace?" Shame on you.
OP mentions Political Correctness and Cancel Culture.
My opinions on those: You're thinking too far ahead. You are thinking of an imaginary event many steps down the line that won't necessarily happen, and that can stop you from intervening in the moment. Ponder over it now if you must, but don't let that freeze you in the moment and stop you from intervening when something is happening.
"Am I being too politically correct...? Am I "cancelling them...?" - who cares. Wrong is wrong. If the individual is coincidentally cancelled in the end, so be it. Trust me, you would have to do far more than just standing up in the moment to "cancel" someone. Just stand up and stop shuffling your feet around.
If the transgressor themselves complain they are being "cancelled" by you, or that you're "being a PC SJW" or whatever it is, ignore it. That's age old. If they weren't saying that, they'd use other excuses. "You're too sensitive," "It's just a prank, bro," or whatever the hell it is. A rose by any other name. Bullshit by any other name, really.