Noel we are splitting hairs..... a song according to dictionary definition is a composition or piece of music suitable for singing......IMO.....technically yes a lyric is a kind of poem.....BUT in the context of songwriting lyrics are words to a song...........how can anyone be a songwriter when they DO NOT write the MELODY.
Putting that aside...my point which you seem to fail to accept is that lyric writers could do much better if they understood ......the most important part...the melody.....JMO
I am also of the opinion that pop music is production driven so melody, lyrics and even performance all come second to production. I do not try to set out to belittle anyone all I am suggesting is that folk learn to play music and learn the basics of music composition, arrangement and production....it would enhanve their skills and make them better songwriters.