This quote from David Mitchell's Back Story highlights the tension between subtlety and straightforward expression in our communication and social norms. It suggests that societies that value humility or discourage self-promotion (blowing your own trumpet) tend to cultivate a more layered, intricate cultural fabric. The idea here is that when individuals are not encouraged to overtly boast or highlight their achievements, interactions and social dynamics become more about reading between the lines, fostering deeper understanding and perhaps valuing implicit knowledge over explicit declarations.

On the other hand, the quote contrasts this with the increasing tendency toward 'literalism'—a cultural shift where meanings must be direct, explicit, and devoid of interpretation or nuance. This "grim world" of literalism could be reflective of certain contemporary trends, such as the emphasis on clear, unambiguous communication promoted by digital communication or data-driven truth claims, but warned against for stripping away the richness of human experience embedded in subtlety and implication.

In a broader sense, the quote invites reflection on how cultures shape conversations and interpersonal relationships. Is a society that promotes explicit self-assertion necessarily more honest or transparent? Or does it risk losing the complex interplay of meaning that allows for art, humor, irony, and deeper emotional connection to flourish? Conversely, could discouraging self-promotion inadvertently suppress individual recognition and expression? The quote evokes the importance of balancing directness and subtlety to preserve a culturally rich and stimulating environment.