The slaves attained high positions in the Ottoman Empire, including several Prime Ministers of the Sultan.

How many black slaves achieved high positions in the European Empires? or in the USA and Canada? When was segregation legal till in European controlled countries like the USA (till 1965), South Africa (till 1994), Namibia (till 1990), Hong Kong (till 1994), etc. Whereas in the Ottoman realms - modern Turkey, there was no segregation against former slaves.

I think there is a false narrative - everyone was equally bad - that is used as a defense for any European crime. I guess everyone in the world was as bad as the Nazis at some point? It would have made a great defense at Nuremberg.