When you were young, as they buttoned you into your coat to go to school, some parent or other oblivious well-meaning wooden adult figure probably told you to go to school, work hard and “be nice to others.”
Like all language, or all tokens if you think about it, the problem isn’t the sentiment of the sayer. It’s the receiver being able to interpret it correctly. Like Bill Clinton’s famous line, “That depends on what the meaning of ‘is’ is.”
What does “nice” mean? I submit it means two entirely different things: to leftists, it means that you are socially polite to others and refuse to obstruct their dreams. To the rightist, it means you care about results.
The right is a complex philosophy. It is organic, and thus not an external ideology. It is based in the idea of consequences being more important than intentions. To that end, it works by comparing known consequences (history) with what is desired, and picking the right tool for the job.
That leads us to wonder what direction we should actually take, which conservatism answers with optimums as opposed to ideals. A liberal will talk about Utopia; a conservative will talk about, given the limitations and conventions of reality, what is is likely to occur and how to make the best of it.
The two definitions of “nice” are completely incompatible.
A leftist will thus value someone who is totally dysfunctional but deferential to others and who avoids stating unpopular truths. Liberal “nice” involves how you interact with others socially, and outside of the individual and the social group, is oblivious to consequences.
A conservative will value someone who states something unpopular, so long as it is true, because conservative “nice” involves avoiding bad outcomes. It puts individual feelings, judgments and desires, and group snowball effects of the same, secondary to outcomes, and defines “nice” as avoiding bad results.
So what is “nice” behavior? It all depends on what the meaning of “is” is.