Theyre not mutually exclusive.

Human communication is impossible to get perfect. You have to strike a balance between a bunch of priorities. I could write an essay on this topic, but nobody would read it. Thus I sacrifice clarity for brevity, and make a comment that can be read in a minute.

If I highly prioritized kindness and told you how much I respected your viewpoint and appreciate your taking the time to engage with me- that would naturally require a number of words. Which means I either make my comment longer- which reduces engagement, or I shorten the meat of the argument- which reduces clarity.

So you can see how these different priorities can come at cost of one another. While I'd like to find the ideal sentence every time I communicate that sacrifices nothing- I just dont have the communication skills to do so.

> If I highly prioritized kindness and told you how much I respected your viewpoint and appreciate your taking the time to engage with me...

... you would be patronizing me, not showing me kindness.

When kindness transitions into patronisation depends on the listener. There are people for whom all kindness in speech is patronising.

What if that problem is "convince your grandma to quit smoking"? It seems that telling grandma she's been smoking away 9 years of her life is somehow "unkind", and yet we all do very similar things as a society, such as putting disgusting images on grandma's cigarette packages, with clear warnings that smoking is a very serious health hazard - and very few people seem to take issue with this or find it unkind.

Fine. Both are bad. What's your point?

I think it's a good point that these "ends justify the means approach" arguments and ultimatums are fully sanctioned by society irregardless of evidence that those who don't change their behavior end up more self destructive, etc thanks to the additional hostility.