Hester, I have never felt the need to be proactive in making sure my children have multi cultural things, and I don't know why you should be surprised at that.
It is enough to teach our children that everyone has equal worth and you should be kind and considertate to everyone. And then to explain, when it comes up, that people come in all different colours, shapes and sizes.
I am not going to go out of my way to teach my children that black people are the same, because they are already taught that everyone is the same and outward differences are just that. I will explain why that is, and reinforce that we shouldn't make judgemnts about appearances, but that goes for fat people, short people, limbless or otherwise disabled people, or people who have decided to dye their haor bright blue.
I will not focus on skin colour, because that turns it into something bigger than I think it has to be.
My dc are both very aware of how ugly racism is, and how hurtful it can be, and they both have close Asian friends. It's not a big deal, and that's the way I think it should be. To teach it any other way creates a divide that doesn't need to exist imo.