Did you read the ending text? It's incredibly long. Are you claiming that people have the entire thing tattooed on themselves? I definitely can't see it fitting on a coffee mug in any readable fashion
Did you read the article? There's a picture of someone with one of the lines tattooed on their arm. Obviously people aren't putting whole poem on things
I think the original point is to say that people felt moved enough by the poem to "permanently" integrate some feature of it into their lives. Critiquing the "whole poem" thing feels incredibly pedantic.
To be fair, some people make tattoos with all kinds of silly things, the bar is pretty low. One can argue that whatever the ending text was, someone would make a tattoo with it eventually.
So then would the artist who created that ending not be entitled to the recognition they deserve for their part in it? If not this author, then another? Would the same story, but from another person change anything?