Maybe anyone can learn to sing, but should they? After all, there would then be hardly anyone in the audience. I went to a local folk concert last night with 5 different groups of performers (about 10 altogether) and barely 20 in the audience.

An English poet, I think it was Samuel Taylor Coleridge, in "Epigram on a Volunteer Singer", wrote;

Swans die before they sing; 'twere no bad thing
Should some persons die before they sing

Actually it is a myth that swans sing before they die (or at any time; the common "Mute Swan" of the British Isles merely hisses, though the Whooper and Bewick's Swans which are winter visitors make a sort of trumpeting sound - I think the Whooper may be known in North America as the Trumpeting Swan, but am not sure). However all this does not, in my opinion. invalidate Coleridge's point.