My understanding is that it's now thought the 'Hanging Gardens of Babylon' was a mistranslation and that they were actually in Nineveh, and most likely Assyrian.
Yeah we actually don't need the Ishtar Gate as a wonder.... It's already kind of included in the Hanging Gardens model.
That seems very similar to the ziggurats Sumeria gets. I still don't know why there's an expectation Babylon will be a science civ - it was in Civ V, but not in Civ IV (though we can't get discounts on Courthouses since those aren't in Civ VI). The policy card and loyalty systems both give options for a 'governance'/code of laws-themed civ, and if you think of Babylonian innovations which have lasted you think of all-permeating cultural legacies such as the 24-hour day and its subdivisions and the 7 day week. That was mathematical but not a scientific advance as such, and like their legal codes better-represented through culture.
They could also have something analogous to Persia's Golden Age ability in Civ V, and for the same reason - to capture the fact that Babylon in Civ has tended to represent a succession of empires rather than a unitary entity.
I did love his personality in Civ V, but Civ VI leaders don't have nuanced personalities so it won't be the same whatever leader they use.
Aside from not knowing why they want a science-focused Mesopotamian civ in a game that already has one, why are people so much less attached to the Babylonians than to other 'starting' civs? Every time a new DLC or expansion was anticipated or announced in Civ V there were cries of "Where are the Zulu?", a much less significant civ whose only claim to Civ fame is that they were in the first game and have been inherited by every other. I always saw that as a desire to have all twelve starting civs as a 'core' common feature of the series, rather than any interest in the Zulu specifically, and favoured their return on the same basis even though I don't feel they meet 'civilisation' standards. So I think of Babylon as being similarly indispensible, while also actually being an important civ.
For me it's a matter of what will add the most to VI and jive with the rest of it's design. VI seems to be aiming to fill out the globe with large, influential powers that vicariously represent the cultural legacies of their region. For example:
We have Persia/Macedon as civs, but represent the Afghan empire with a city-state.
We have Georgia as a civ, but Armenia as a city-state.
We have Poland as a civ, but Lithuania as a city-state.
We have Hungary as a civ, but Bohemia as a city-state.
We have England as a civ, but Ireland as a city-state.
The purpose of this sort of "cultural consolidation" is two-fold. For one, it allows the devs to spend fewer roster slots on denser parts of the world and open resources to cover new parts. For two, it overall makes for more diverse game design, as the roster overall pulls from more diverse cultures, and tends to include similar cultures less.
As far as I can tell, the choice to include Sumeria led by Gilgamesh was intentionally devised as a way to vicariously represent the entire Mesopotamian legacy. Akkadia and the post-Akkadian empires all saw Gilgabro as a culture hero and viewed themselves to some extent as successors to Sumeria. We've noted elsewhere on the boards that Sumeria does have a lot of Akkadian things about it's design as well. And I would argue that Sumeria was mechanically designed as well to be as sort of Ur-example hybrid of Babylon and Assyria, where it gets river bonuses and a science/culture ziggurat, but also some miltaristic and diplomatic bonuses.
Point being is that Sumeria seems intentionally designed to half-incorporate elements from the other staple civs in a way that leaves the region feeling overall represented. But this also has the consequence of preemptively stepping on the toes of any new additions if, say, later down the line the devs want to add Babylon. To try to develop Babylon now (and especially after the Mayan tall/science design) would likely move design into the esoteric and unintuitive.
Now, I'm not saying Babylon (or Assyria) won't happen. It is a fan favorite and would be easy money for Firaxis. However, by the game's self-obvious design, Babylon isn't really necessary to complete the whole picture. Whereas something like the Timurids, Morocco, or Oman/Swahili might be more highly prioritized for the aforementioned reason of representing large, culturally distinct regions. Babylon falls more into the "Austria" category, where Germany and Hungary do just fine showing off that part of the world, but just the name Maria Theresa is still a massive draw. They are extraneous, but would still make excellent bonus content and are almost certainly being considered and/or developed.
So while I view Babylon as likely, I don't consider it necessary. Not with this particular iteration of Sumeria in this particular version of Civ. I would note, however, that if we ever get clone or semi-clone civs, it would be really cool to see Sumerian assets split down the middle and have one half built out into an Assyrian civ and the other into a Babylonian civ. That would be a cool way of adding what players want but also maintaining VI's cultural legacy angle.