Jeri --I guess it's just perspective. I switched from Puff and Pooh (gosh, said like that, it almost sounds obscene!), to more 'generic' magic because I wanted to allude to stories older than the twentieth century, to reinforce the line(s):
But every tale of magic
that's been told throughout the yearsPeter Pan was written in 1901, The House at Pooh Corner in 1928 and Puff the Magic Dragon in 1963 -- that's not a lot of years, really. Especially since, even by the time the Pan was written, magic had become "quaint" -- silly, and impossible.
After all, that's why Barrie called the main setting for his story "Never-Neverland", because it could never really happen, could it? :-Þ "They" that are speaking in those first verses want to relagate magic to Neverland, the Hundred Acre Wood, and Honnalea (how is that spelled, anyway?) because these places are fictional. Whereas in the older wonder tales, magic is treated as being very real.
As to the "mothers' blessings" lines, I wanted to convey the the worldview of the naysaying speakers in the first half -- that no amount of love or well-wishing (and no love is stronger [usually] than a mother's love -- even an emotionally clumsy and dysfunctional mother) has the power to help you, and that's why you have to grow up and fend for yourself.
I also had in mind specific incidences from certain tales where a mother's blessing was the critical magic on which the course of the story turned. In the older versions of "Cinderella", for example, it wasn't a 'fairy godmother' that gave the heroine the magic to get to the ball, but the spirit of her own mother, who lived on through a hazel tree which grew over the grave. When the heroine's mother lay on her deathbed, she blessed her daughter, and told her how to plant said tree. And in the story "The Goose-Girl" the mother gives her blessing in physical form: the last thing she gives her daughter before sending her off to a distant kingdom to be married is a white hankerchief with three drops of her own (the mother's) blood on it -- sort of like a medicine bundle. As long as that handkerchief is tucked in the daughter's bosom, she is safe from all danger (naturally, she is tricked into losing it, or there'd be no story ;-)).
But trying to put all those details into the verse would really mess up the scansion. ;-)
Besides, for me, I have a stronger personal connection to those older tales. I cut my bookophile teeth on Mother's copy of Bulfinch's Mythology -- there weren't many pictures, and they were only two colors, but when I was 4 years old (maybe 5), I was fascinated by them, and would lie on my parents' bedroom floor, flipping from one picture to the next. The Winnie-ther-Pooh books were read to me before I got around to actually reading the myths for myself, but I had a subliminal knowledge of them that formed a sort of backdrop to the more modern fantasies.
Gee... I babbled on far longer than I expected to. But in any case, the above is the reason my milage varies...