an architecturally mundane Gotham
My understanding is that it was mainly Chicago and London that stood-in for Gotham. And I've never heard either of those cities described as "architecturally mundane."
Your "understanding is"... so, in other words, you don't know for sure/didn't recognize Chicago or London while watching the movie, thereby suggesting that Nolan shot fairly nondescript urban locations in those two cities. And yet I'm the idiot for supposedly calling those two actual places, which we barely saw in the movie if at all, "architecturally mundane".
Riiiiiiggght.
You're certainly not an idiot (nor did anyone call you one), but you can be very smug towards people who disagree with you sometimes, and often for no justifiable reason, like now. You often seem to stake out an unpopular opinion (which is fine) but then look down on any one who questions your reasoning, even if they do so politely.
I'm sure he said "my understanding is" in case there were more locations used besides Chicago and London (which there were), but he's absolutely right that those were the two primary filming locations, and there are several architecturally distinctive or recognizable features from both cities and others nearby in 'Batman Begins' (and 'TDK,' but I won't get into that too much):
Mentmore Towers in Buckinghamshire, England is Wayne Manor, which was in one of your favorite movie series in 'The Mummy Returns' as the O'Connell's mansion. It's also in 'Eyes Wide Shut' (the orgy house) and 'Brazil':
Wayne Tower was the Chicago Board of Trade Building, which was the tallest building in Chicago from 1930-65, and was the site of the trading floor scenes in 'Ferris Bueller's Day Off':
Coming off the Board of Trade Building, the ominous LaSalle Street "Canyon" was used in both Batman films, as well as 'Road to Perdition,' 'The Untouchables,' and 'Public Enemies':
The opera house where Bruce's parents were murdered after leaving the show is Garrick Theater in London, financed by W.S. Gilbert of Gilbert & Sullivan:
35 East Wacker or the Jewelers' Building is Gotham's Courthouse:
The Port of Gotham was the Tilbury Port in Essex, England, which also doubled as Venice in 'Indiana Jones and the Last Crusade':
The exterior of the restaurant Bruce bought was CityPoint in London, which also appeared in '28 Days Later':
Seen in the foreground is the Franklin Street Bridge, which is the one the Tumbler jumps to get to The Narrows. To the right, the distinctive twin condominium towers of Marina City were also visible in the film. They're in pretty much every establishing shot of Chicago on film ever:
The foreboding National Institute for Medical Research (NIMR) in London was Arkham Asylum:
And finally there's Lower Wacker Drive, which was featured prominently in the chase scenes involving the Tumbler in both films:


So, yeah, they didn't use impossibly high poorly constructed Gothic wood and stone mega-skyscrapers like Burton's Gotham, but I'd hardly call it architecturally mundane and unrecognizable.