When you can say whatever you want and don't care too much, isn't it important to talk to others?

There is nothing important to tell others, but you can't say whatever you want, and you can't just say it without considering anything. That won't do either. People should be sincere and respect each other. When you speak, you should consider each other's feelings, instead of saying whatever you want, as you said, which will affect your feelings, so whether you have it or not.