[Open Comment Thread] Why Are Original Keys So Darned High?

Often readers send me questions to ask publicly on the blog, since the superior hive mind of the CPB readership is incredibly diversified and eager to hold forth on matters of interest to the collaborative field.

Doug MacNaughton asked the following question about composers and key choices in art song:

Why is it that the default original key tends to be for the high voice? For women, I understand, as the Soprano is the most common voice type, but for men about 70% of singers are Baritones. Why did Schubert, Schumann, Wolf, Faure, Debussy et al write so much of their rep for the high voice?

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