"I've never seen such before, where might one find such a range hood model?"

Elica, Faber, and Zephyr offer these. Scroll through the pages at build.

and what it does capture, I can only imagine that the flat part would get icky pretty fast and cleaning it would be a dangerous pain.

Given the amount of space dedicated to displaying a half dozen bottles of wine without temperature control, I think it's safe to say the kitchen errs on "form" end of the form vs. function spectrum. Range vent hoods aren't required by code where I live, and while the one in this kitchen won't do much, it could be effective at venting moisture, at least if the occupants bother to turn it on.

The first ceiling mount range hoods I remember seeing were very large, like this 48" Faber (I think I have even seen 54"), for over a 30" or 36" cooktop. (18" wider vs. 6" wider)

which I guess is to increase the capture area because of the expanding vapors as they get higher and higher. But none of them seem to be that much deeper from front to back.

Miele (or perhaps Gaggenau) once sold a larger retractable island hood. I don't recall the range of movement, but I don't think it went all the way up.

If the kitchen is for show and not cooking then anything will do. If you'll use the range for actual cooking then a proper overhead exhaust hood is needed.

More: https://bamasotan.us/range-exhaust-hood-faq/

Thanks for all the comments. It will be interesting to see how fast the house sells and who actually would buy a house with such kitchen. Whether it's just a show kitchen and the owners eat out or order takeout, or whether new owners will remodel and change out that range hood.

Quite honestly, there are a lot of people outside this forum who If they have a range hood they either never turn it on, or only turn it on if they burn something or cook something that really stinks. It's not nearly the deal breaker as people in this forum make it out to be in my experience. (and my SO is a former chef and real estate agent, so I get a lot of intel on the kitchens, and on why or why not something sells, and I don't think I have ever heard "it didn't sell because it didn't have a range hood/ had a microwave range hood/ had a recirculating hood instead of externally vented". I can't think of this happening a single time, and we talk about the transactions in detail.)

I would never design a kitchen without one, back when I actually designed a few kitchens for other people and I asked them if they used the range hood and those were the answers I got from everybody, "never to occasionally".

I even turn mine on if I am cooking something in the oven unless it's something with cinnamon in it.

I would expect most "everybody" to have only experienced noisy ineffective ventilation schemes and developed an aversion to turning them on as a result. My advice to them is (a) hire a Chinese student to cook a meal for them in their home, then, the next day, while cleaning the ceiling and walls, contemplate the zen of ventilation, and (b) try to find someone with a real ventilation system to demonstrate functionality, or just observe inside any quality Chinese restaurant the lack of overwhelming odor and smoke, and outside the restaurant the monster up-blast roof blowers and the (typically horizontal structure with angled face) make-up air intake/conditioner.

One's need for ventilation performance obviously must be scaled to the effluent production rates and intermittencies that will be experienced, and performance translates to size and cost. Most residential kitchens have too low a ceiling height for commercial hoods, and some aesthetics demands will be applicable.

We have on this forum outlined in many threads the means by which good capture and containment can be achieved if it is desired and affordable. I think the dominating limitation is ignorance of the topic, which was my state of knowledge in 2007. But the information is out there, and I think I have seen over time here a gradual increase in recognition that effective kitchen ventilation is an issue to be addressed as best one can.