I heard a young black man say "that white man did what he had to do!" I have no idea how it applied to the smoked salmon salad he was replicating.

I asked Chatgpt & Google for meaning and historical context. I'm not comfortable with responses. Can someone explain?
https://chatgpt.com/share/67a1dae6-75a0-800b-bfc4-286a0ad5bf66