My brother doesn't think I can be a social worker

I'm 18 and start college next year! I'm planning on being a social worker and I'm so exhausted. I planning on making a difference. My brother is a social worker and he always talks about how broken the system is. It's why I won't go and make a difference for the people, children, and system. My brother told my my mindset is gonna cause me a lot more trauma and heart ache. His words were basically "People who go into social work thinking they can change the world usually get burnt out the quickest. You have to have realistic expectations and realize while you may be able to help some people, a lot you won't be able to help because the system is broken. We can't individually fix a broken system." He said it nicely but it felt like he was trying to put me down. He's honestly always felt like the family favorite and my brother is kind to me never mean but I wonder if he thinks he's better than me.