There was a big problem in BG3 for Fantasy settings that should be avoided in the next game Divinity. The Absence of Cultures of Fantasy races, their traditions, their differenсe in lifestyles, their homelands. If we replace all the main characters, minor and background characters with just humans - nothing will change in BG3, except few names.
To be fair, Baldur's Gate is set in (And around) the city of Baldur's Gate. Which much like how real life cities such as New York are a melting pot of many cultures, is likely to end up having its own culture form as a result that is somewhat different to all the original cultures that emmigrated to it.
That combined with the rarity of travel/relocation means that many Baldur's Gate citizens would have lived in Baldur's Gate for their whole lives and likely many generations.
As such, the lack of diversity is somewhat expected. Since if everyone has the culture, traditions and lifestyle associated with Baldur's Gate, then it would be reflected by everyone acting very similarly - With a few minor predjudices here and there because racism...
That said, it was quite noticeable with the Tieflings. As they are specifically mentioned to have come from Avernus. But they don't act any different to anyone else. Which is pretty disappointing and made me miss Woljif from WotR, where he had a tangible reason for being so heavily discriminated against (He was born to human parents. But came out as a Tiefling due to his grandmother getting it on with a devil. He was subsequently abandoned by his parents and forced to live with his grandmother who despised him, leading to him running away and living a life of crime on the streets). Meanwhile, you can't even tell the Tieflings came from Avernus, let alone understand why people are so heavily predjudiced against Tieflings.
Divinity announcement trailer showed exactly the same mistake, all of the Fantasy races are mixed in the salad again around small human city... I understand, the point of the announcement trailer is to show the major lore concept without any details, to show the playble races - elves, dwarves, lizards, humans, orcs. The "Salad" should(Must!) be avoided in the actual game and story!
I don't think it should be completely avoided. It's only natural that eventually mixing will occur between races. It's unrealistic to expect every single race to be vehemently traditionalist forever. Especially when there will be major trading cities that will thus become a melting pot of cultures just like Baldur's Gate and many real life cities (Which don't always have segregated areas specifically for different cultures)
Having some places still holding on to tradition, especially towards the centre of a race's territory, makes sense and would remain largely populated by that race (Of course, travellers, guests, traders etc. Will be mixed in). But towards the fringes you'd start to see more mixing as major trade occurs, as well as things like alliances, embassies and other political endeavours (Unless races are actively at war with one another)
The main goal would be to have players visit a selection of locations. Some deeper in a race's territory and so more traditionalist and thus more insightful into their racial heritage, some more towards the fringes where cultures have melded and you now see something unique that is shared among all the inhabitants of the city regardless of race.
Hopefully their quote for this new game being "Larger and deeper in breadth and depth than ever before" will mean that we do get to visit a variety of locations. Meaning we can get a much wider and deeper look at each races unique culture deeper into their territory, whilst also getting to visit large trading cities where cultures have mixed.
