You're right. Labels can be harmful. I agree that everyone is a person and deserves equality. At the same time, ya gotta admit that at this moment not everyone is equal. There's still a lot of prejudice towards LGBT+ people. In a lot of places you can lose your job because you're a transgender person. And beyond that we still have social systems that favor straight white cisgender men. We've made a lot of progress to be sure! I'm not saying that racial and sexual prejudice are at the same levels they used to be, but it wouldn't be accurate to say that racism, sexism, and LGBT+ oppression is over. tl;dr labels are useful for defining and explaining the oppression that still exists today, in the hopes that we might end that oppression.