Its completely age appropriate 5yrs old is when kids start enforcing social norms. If you don’t talk about race directly society will cover it for you and you might not like what comes up. In How to not raise kids who are assholes she goes over the science behind it. You want to be direct and tell her your thoughts and feelings, the “everybody is the same lets not talk about it approach” doesn’t work.
How to Raise Kids Who Aren't Assholes: Science-Based Strategies for Better Parenting--from Tots to Teens https://www.amazon.com/dp/B08NWXYMJN/ref=cm_sw_r_apan_806G35PT93XB6QN3HNKK