> Adequacy of the hood seems like it's not going to be usefully quantifiable or provable

If we can't come up with something a little more scientific I'm happy to send my wife over to do some cooking!

The effectiveness of the range hood directly impacts how close you can be to the stove before your eyes start burning and watering and you start coughing a lung out because you've effectively been hit with pepper spray.

In the worst case scenario (no range hood or ventilation), you'll probably want to evacuate the house.

As the person you replied to says as well, the popularity of "open concept" spaces contributes too. Even with poor ventilation, a kitchen with a door you can close helps limit how far the cooking byproducts reach.