What's the theme in paragraph four as related to the whole poem "Railway Club Blues" by Pete Trower?

Throughout the poem, Trower examines how jazz music unifies the older generation fans with the
new generation of young punk rockers. In the last paragraph, Trower writes that the
"cardboard boundaries are erased" after the two different groups of people listen to
harmonious jazz music in the same club. Throughout this paragraph, Trower explores the theme of
unity through the punk rockers' reactions to the jazz music. On the surface, the older
generation of jazz fans has nothing in common with the young punk rockers. Despite their
differences in appearance, there is a common attitude and preference for jazz music. At the end
of the poem, Trower...