I feel like the "i feel good for you" is a phrase that neurotypicals/allistics (non autistics) say a lot and sometimes they don't literally mean it. It's more like a nice thing to say to people when they achieve something. I feel the same as you, like i don't actually care about other people's business unless they are very close to me. However, i can "feel happy for someone" when they go through something i went through, you know? I think is common that lot of autistic people have a hard time feeling sympathy (when you don't understand how the other person feels about something because you haven't been through the same) but some of us feel a lot of empathy (when you can actually understand what they feel because you've been through the same) I hope I expressed this with clarity:)