For the intimate revelations of young men, or at least the terms in which they express them, are usually plagiaristic and marred by obvious suppressions.
“Plagiaristic” in the sense of being borrowed from other sources and role models more than lived and felt for themselves. For example, a young person might confess to being “in love” without really knowing what that phrase means; they may only be hyperbolically applying it to puppy love.
“Marred by obvious suppressions” — as in, they clearly aren’t telling the whole truth.
In other words, these “intimate revelations” aren’t really all that intimate or revelatory; they’re a little boring.
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