Guest Acorn4 said above 'don't you just DREAD that top note in situations like this?'

I dread it all the time.

The melody for this song was around long before the words 'Danny boy' were penned. I doubt if the melody was intended for voice at all. It was probably written for an instrument such as harp or violin.

(I believe the words were written by an Englishman during the era known as the Celtic Revival.)

Either that, or this possibility. There used to be a tradition where a man sang one part of a song in his normal voice and then leapt to falsetto-countertenor [whatever you want to call it] for the next. That may have been what the composer had in mind for this song. But in that case, why are there no original words?

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I have a suggestion for those singing the song. Our church choir had a visit from an expert, who pointed out that it is perfectly possible to come to a high note and sing it SOFTLY. I had never thought of that before. However, I've practiced it, and is possible to sing a high note and sort of 'aim it at the floor,' minimizing the effort and the impact. I believe this would work for Danny Boy.

How important is the word 'here' anyway?

Fortunately, my crowd doesn't do music like Danny Boy. We are not into Victorian.