Why are mezzos nicer than sopranos?

It is a truth universally acknowledged that cellists are easier to get along with than violinists. The first to tell you this are, of course, cellists, but a lifetime’s association with both species confirms that the guys and girls on the lower strings tend to be gentler, sweeter, more agreeable than the more nervous, fractious players on the high wires.

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The same truth applies, on the whole, to female singers (though not, necessarily, to male). Every mezzo I have ever come across or worked with has been a privilege and a pleasure, some developing into lasting friendships, others parting in mutual respect. Never a harsh word, so far as I can recall.

Sopranos, on the other hand….

Now, why is that?