It takes time and it smells.
Where I live cheap frozen pommes frites costs about the same per kilo as washed good quality fresh potatoes, and personally I think slicing and putting them in the oven with butter, salt, black pepper and herbs is much tastier than fries. To me it's worth the effort.
My stove fan vents straight back into the room. Anecdotally maybe 75% of friends whose stoves I've observed do the same thing.
It's a travesty as far as I'm concerned, but there you are.
(I live in an apartment; otherwise you can bet I would have done something about it before now.)
If you didn't check and put one yourself, you might not even have a carbon filter at all.
But in all cases this setup is totally insufficient for frying things without stinking the whole place.
Yes, unless you have equal amounts of outside air entering your domicile, a vent leading outside is not effective. A recirculating vent, however, still has a filter.
Hood filters capture airborne grease, smoke, steam, heat, odors, and other substances that are produced during cooking under the hood. Without the proper hood filter, your kitchen will be filled with airborne particles you don’t want your staff breathing! [0]
Not leading away moisture from the kitchen when cooking doesn't sound like a good idea to me but I'm just a child of a craftsperson working with these kinds of things, not one myself. Except if you live in like a hut with a lot of openings or something, but I'm kind of assuming this is about apartments and houses with isolation and so on.
Here in Belgium people just go to the nearest fry shop for their fries, they're better than home fried and it's easier and faster.
Since I'm not Belgian myself, I cut my potatoes into cubes and fry them in duck fat with rosemary instead. It's a whole other level of stink though.
Something like this:
https://www.swedishfood.com/swedish-food-recipes-side-dishes...
Related: why is it so hard finding a house with a range hood (and not the useless recirculator with carbon filter)?
Now none of that is a great excuse, it isn't that hard to do, but with how most buildings are subcontracted out piece by piece for every little part, and how some things like the kitchen appliance location is not super well finalized until cabinetry is actually installed, nobody before the cabinetry wants to take the responsibility of is positioning and the cabinetry guys are not expected or expecting to install such features.
It is time, expense, and the liability of punching a hole in the roof before someone decides they want the stove on the other side of the room, or coming in months afterwards and punching a hole in a brand new roof as someone not the roofer. If everything is well established in the blueprints and nobody is going to be changing their mind, or if one guy/company is doing 90% of the work themselves its not a problem. But often things are changed kitchen wise after most of the house is built or is done by 10+ different contractors, none of which want to be held responsible later on for it. Often one company does the structure, another the roof, another the siding, another the drywall, another the plumbing, another the electrical, another hvac, another cabinetry, etc, and only the plumbing and furnace vents are going to be putting holes in the roof which happens long before any finished features like the cabinetry is put in.
However currently there is a movement to (more expensive, luxury) solutions that do not have a vent hood and instead vent through a recirculation filter (Bora).
However, two friends who love to cook or have an SO who does have had full outside vented range hoods installed when they remodeled. One is so serious they have a commercial hood over a 6 burner stove. That guy brings his own lunch almost daily complete with their own fresh baked bread. His SO has a library of cookbooks and enough kitchen equipment to feed an army.
There's also the belief that it will somehow break the main ventilation motor because of the large volume of air forced through it. But it shouldn't actually be a problem.