A lot of this feels like a Ship of Theseus debate.
Yes. And there are a lot of people in the world who - often unconsciously - believe race is an essential part of a nation, whereas I believe it is a social construct that was created during the colonial period for economic and political power.
So, when my Civ changes from predominantly Greek to predominantly Spanish to American, it does, honestly, surprise me and reduce my immersion a bit. But I like the historical realism and the gameplay choices. But for me, it's exactly the same as when my Persians become Aztecs.
This game is deeply opposed to essentialism of any kind. Much of the controversy is really about philosophy, and not videogames.
There is:
State essentialism - a civilization is only the same if it is the same State. Italy is not Rome, France is not the Franks, Iran is not Persia, Russia is not Nordic, the USA is not European.
Historical essentialism - the world could only have turned out this way.
Geographical essentialism - Persians are nowhere near Normans so how could they change.
National essentialism - the Han people are fundamentally different from the Dai Viet.
Racial essentialism - Greece becoming Spain is fine but Normans becoming Meiji Japan would not be.
Me, I stand with Vision. The Ship of Theseus doesn't bother me much. My life has been liminal - I'm tri-cultural, and an immigrant child of immigrant parents. Despite being whiter than Snow White.
But I am sympathetic to people who find 'Civilization 7 - Ship Of Theseus Edition' jarring and unappealing
if they accept that I'm not wrong for liking it.
That is the key thing I've taken from here. The people who are anti Civ-switching don't seem able to accept that anyone could actually like it or not mind it. And while, from a business POV, it matters if we are a tiny or significant percentage, that is not something we users should care about, except as consumers who might want more support in the future.
Essentially, this is all about essentialism.
