From the examples I see on Twitter, they are usually referring to the different cultures of Irish, European, and American white people. Gemini, in an effort to reverse the bias that the models would naturally have, ends up replacing these people with those from other cultures.
Since the definition of "white" is inherently cultural, it varies from place to place and from time to time. Today, in US and Europe, pretty much everyone who cares about racial categorization would consider Irish "white". Historically, it was different, but that is only relevant when discussing history.
Isn't it even more racist to replace them in a picture? Being told that your skin colour is too offensive to show sounds a lot worse to me than calling them "white" considering their skin is very white
US American white people. Anything else would be a ridiculous overgeneralization, like "Asian culture", even if you set some arbitary benchmark for teint and only look at those European countries it's still too much diversity to pool together.
As if you can generalize the culture of different European countries, or even different regions in the same country just by skin color. Now this, in my opinion, is a form of cultural erasure where all the intricacies and interesting aspects of culture are put aside and overshadowed by skin color.