Listening, being respectful, and being empathetic may drive one person to bite their tongue and silence feedback that someone is performing poorly out of fear of hurting them or the morale of the team. Another may be driven by the very same things into giving candid feedback.
This article does not do a good job of exploring the difference. It just asserts "Being nice is the new punk".
I've worked in very competent teams and very incompetent teams. There were two types of incompetent teams. The type that always denied making mistakes, and the kind that owned up to their own incompetence. Being kind leads to the latter.
It still sucked being in an incompetent team, but when they admit their weakness, they get out of your way and defer to you. When they don't admit it, you'll face barriers all the way.
Being kind to a person that behaves as described in the grandparent comment could communicate that you find this kind of behavior helpful. Fine if that's really the case; problematic for everyone if not.
This entire discussion needs to come to a screeching halt while people get together and hammer out some definitions. It's clear we're all working from different and contradictory assumptions about what these words mean.
I think most people would agree Fred Rogers was kind - but I have to imagine he had to fire people from the show over the course of its run.
If someone is fucking up, they are in the wrong position. People need to work for a living, and shouldn't be under duress constantly. It is up to them and their manager to find a position that is rewarding and engaging for them.
If they don't care, they are also in the wrong position.
It is no reason to not treat them with kindness. You don't have to blow them, but you don't need to be UNkind, as several have said below.
The only people I don't treat with kindness are people who are legitimately trying to hurt me and people I love, or promote hateful ideas with glee. People who are failing at their job need help.
And if they still annoy you, then I think the problem might be in how you view the situation. Compassion helps with anger. Try to think about why you are so angry, and if it really matters or helps to be so angry. Especially if you are not the manager. If you are the manager, consider that maybe the job isn't for you. You shouldn't be pissed at work all day!!
A business is not a charity.
(I don’t know you but you sound like every white male teenager who discovers Ayn Rand.)
If you're a leader with a strategic role, time is your most important and limited resource. You just cannot afford to spend time on something that doesn't further the goals of the business, even if you're a hippie or a communist.
Moreover as an IC there is a lot you can do; most importantly you can quit if you feel the team you're in is being mismanaged.