Because that's relevant. Why not ask how many Monte Carlo owners know where Monte Carlo is?
Monte Carlo was just a name. Denali is an obvious metaphor for that the vehicle trim level is. Perhaps I should alter my question to "...what the Denali is".
But to your point, I'd say a good deal of people knew in the early days what Monte Carlo is, even if they can't exactly pinpoint it on a map. Monte Carlo was much more promenant in popular culture in the '50s~'80s. I have nothing good to say about post-'88 Monte Carlos, so I'd have to assume their owners don't even know THEIR addresses, let alone where Monte Carlo is. ;-) They only know that #3 Dale Sr. drove it to glory.
On that note, let's get in our Delorean and ask people who bought an Eldorado Biarritz what/where Biarritz is. I believe that is equally a metaphor similar to Denali as you put it.
Or better yet, "Brougham" since that was an uplevel trim used on many, many different marques.
From Wikipedia:
In the 1930s, a brougham was a two-door or four-door sedan, especially one electrically driven. The term was also applied to a vehicle similar to a limousine but with an outside seat in front for the chauffeur and an enclosed cabin behind for the passengers. The name derives from the light, fashionable brougham carriage of the nineteenth century.
Cadillac first used the name on their Cadillac Brougham in 1916, and on their top models throughout the 20th century.
Over the years, Cadillac, Buick, Oldsmobile, Chevrolet, Pontiac, American Motors, Mercury Lincoln, Chrysler, Plymouth and Dodge have also used the Brougham name to differentiate the more comfortably-appointed versions of a given model; Chevrolet Caprice Classic Brougham, Pontiac Parisienne Brougham, Oldsmobile Ninety-Eight Regency Brougham, Oldsmobile Cutlass Supreme Brougham, Chrysler New Yorker Brougham, Plymouth Valiant Brougham, and Dodge Monaco Brougham have all been produced. American Motors' top line Ambassador was marketed as the Brougham in 1971-74.
Ford used the Brougham name on its 1970s-era LTD and Torino lines as well as the Mercury Marquis.
Also I do know that Daewoo had a Brougham model as well.