Those who interpret this poem as suggesting non-conformity take the word “difference” to be a positive difference. But there is nothing in the poem that suggests that this difference signals a positive outcome. The speaker could not offer such information, because he has not lived the “difference” yet.
The other word that leads readers astray is the word “sigh.” By taking “difference” to mean a positive difference, they think that the sigh is one of nostalgic relief; however, a sigh can also mean regret. There is the “oh, dear” kind of sigh (sigh of regret), but also the “what a relief” kind of sigh (sigh of relief). Which one is it?