What is the speaker's attitude to Buffalo Bill in e. e. cummings's "Buffalo Bill 's"?

The speaker starts by referring to Buffalo Bill as “defunct,” or dead. Straight away, we’ve been placed on notice that this is going to be an irreverent portrait of an American hero. That said, the speaker does still admire Buffalo Bill for his remarkable skills as a horseman and sharpshooter. He also praises his good looks; this is a “handsome man.” Yet the tone of irreverence soon returns. The speaker belittles Buffalo Bill by taunting the figure of Death:

how do you like your blue-eyed boy Mister Death

The speaker’s alive; Buffalo Bill’s dead; this gives him a sense of superiority over a legendary American hero. Despite his wealth, his fame, his dashing good looks and showmanship, William Cody ended up the exact same way as everyone else. The speaker wants us to reflect on the transience of life and uses a revered figure from American history to illustrate the point.
https://www.poetryfoundation.org/poems/47244/buffalo-bill-s