Yeah I've met at least 5
James that are age 25 and younger and none of them go by
Jim or
Jimmy or any nn.
James is short enough that it doesn't need a nn plus all the
James nn's are very dated sounding but
James is not dated. So you are actually more likely to met a young
James without a nn than you are to meet a
James nn
Jim or
Jimmy.
I know one
Andrew that doesn't go by a nn. Only the names you listed that are longer than two syllables will be harder to get away with not using a nn. All the two syllable names I wouldn't worry about.
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