You make it sound that the brits were the bad guys, when it was an elite top % pulling the strings and the rest were mostly trying to make ends meet.
But yes agree, the elite extracting wealth from the colonies back in the days, and still are extracting wealth from your average Joe, deserves far worse.
Colonies can only address this at the granularity of the nationalism with which they were presented. If every-day brits don't want to be blamed, they need to make their own rebellion to show they aren't party to the evil done in their name.
I think this is true of my own country (the US), and it's hopeless. I think most americans are ok with the evil done in their name. I wish I had better advice or insight.
But pretending like two imperial powers arguing over greenland is some great injustice just spits in the face of humanity. Have some fucking dignity. Greenland deserves better than to be treated like a piece of property