I have the same reaction to Banksy, and figure he and his audience just have to be in on the joke? I can’t discount there’s some layered irony going on in conversation between the artist and the intellectual / capitalist / trend-setting elite that are his effective patrons.
“I remember when all this was trees” [1] is maybe the best example. Detroit hasn’t been “trees” in something like two centuries. Platitudes doused in treacle.
[1] https://www.usatoday.com/story/news/nation-now/2015/10/01/ba...
A better example of a knowing joke between artist and establishment would be the auction of a Banksy work on paper poised above and within the jaws of a paper shredder .. that was then half shredded on the fall of the hammer and sale.
For clarity, the shredder was part of the work and the sale was of the half destroyed piece along with shredder and chaff.