The harmonization of the chorus of David Bowie's single Ashes to Ashes is simply inept - turgid, glutinous, suffocating (against the meaning of the words). From 1:00:
But actually the harmonization is pretty bad throughout, there is a sense of the whole thing collapsing under the weight of sheer thickness of texture .
At times, indeed, it is almost as bad as Brahms (heh).
Contrast what good harmonization can do: The chorus of The La's on the phrase, which is also the song's title: There she goes - this is the only thing that makes the song memorable, and the only thing that makes the chorus good is the way that the harmony opens out.
(Actually, the way that the lead singer moves into falsetto as the melody rises is another positive element.)
Or Duran Duran's Girls on Film - when, again, the title-chorus is good almost purely because of the harmony (from 0:50):
Conclusion: Good pop songs are not just about melody and rhythm - but harmony sometimes comes into it too: just think of the Beach Boys or The Beatles.