Ive always liked this song
Yes, the words are a bit mind numbingly simplistic and a bit annoying after a while, but for me the wonderfully constructed song that it is more than makes up for it.
I think of The Jacksons song ABC and that too had a wonderful melody & construction.
Paul had a knack of writing some songs that sounded simple but were in fact quite complicated in their structure, Penny Lane comes to mind as well, another bright and breezy well crafted song, although in this case with great lyrics.
Probably my favourite bit of HG is the very beginning - YOU SAY YES !! .............kind of slaps you in that face, it really is a great opening, and the chromatic run down the piano scale when Paul sings "I say Go Go Go" is really nice.
Apparently John dismissed Hello, Goodbye as "three minutes of contradictions and meaningless juxtapositions" and he may have had a point, surely his Walrus the better of the two, quite an outstanding piece of music, monumentally new for its time and massively influential.
I remember in Britain it was treated as a double A side really with both songs getting loads of airplay.
Its no classic, but a piece of very well crafted pop music.