Greece is one of the key foundations of Western European culture, and Steampunk celebrates a recent age of incredibly inequitable imperialism. My European side highly values the rich elements of our culture from the many sources. Another side, looks with mild despair on how thoroughly certain narratives are recited. The point we're at, I feel we could be celebrating every effort to be diverse, and avoid undermining or digressing from them from the outset. No matter how subtly.
Steam punk celebrates technology and and a style, not imperialism. Nothing in steam punk culture celebrates imperialism or colonialism, like abuses of various cultures.
All culture have dark periods all of them. Japan has world war II, the FN Miq'mac wiped out the FN tribe in Newfoundland, many African Empires sold slaves, Ghana apologized for this, even though no one living had any part in that. Feeling guilt at ancient crimes is absurd, all guilty parties are dead.