Lady Bracknell is mocked in Oscar Wilde's play The Importance of Being Earnest by reuniting all the characteristics that are most common of the fashionable and aristocratic Victorian society: Flippancy (arrogance), haughtiness, ignorance, sarcasm, oblivion about reality, and their hypocrisy.
In Lady Bracknell we find most of these in a very heightened tone. For instance, she is clear and brutally honest to Jack that she refuses to marry her daughter to someone of lower status, even if that person is he. Therefore, what does she do? She takes out a notebook where she has written a number of questions regarding finances, asking all kinds of pretentious questions about money and other shallow issues.
Additionally, her language is exaggerated as if trying to appear to be more aristocratic than what she really is. One must wonder if the Bracknells are actually what they make themselves out to be, considering Lady Bracknell's preoccupation with Jack's possessions. In the end, what matters is that she represents a stratum of society that is notorious for having too much and knowing too little of anything else.