Sometimes I think people get all tied up trying to find similarities between dissimilar pieces of music.
My sentiments, exactly. I surely couldn't get the text to scan. And even the "Love Somebody" lyrics fit the "flattened" version of the tune better than the shall we say "arpeggiated" version. I think of the tune to "Soldier's Joy" as (using degrees in the scale instead of letter notes):
(6)_5_3_1_3_5_3_1_3_5_8_8, etc. When I sing "Love Somebody," I sing it
(6)5___3___1___3___5___8_8 (not sure how to show this, but essentially, it's half the number of notes)
I think of this "flattened" tune as the American or Appalachian version, and the arpeggiated version as the Irish/Scots or even "Colonial" version. I think of it, then, as the older one, and hard to sing to, also.