You say that something is nice when you are being genteel. Being nice is not necessarily caring or good. Nice is an auto-response.
Being kind is an intentional act. Kindness is an authentic way of being.
Niceness is construed. Benevolence is grounded in action. Niceness is performative.
Social norms require niceness. Niceness is saying “Happy birthday“. Altruism is going out of your way to make a card.
Kindness is service, it is doing something instead of complaining about how terrible things are. Niceness is saying how much better things once were and how we should do something else (and liking the posts where everyone agrees).
People tend to do nothing because they are afraid to hurt someone’s feelings, not understanding how unkind that is. Sometimes you need to be uncomfortable to grow, and nice silence allows for festering echo chambers to destroy mental health.
Challenge yourself to be kind to yourself (first) and those around you (second).