He doesn't actually use the word 'gatekeeper', but it seems to me that in this article from the Guardian, Anthony McGowan is also writing about the problems of delivering books - either as a publisher or a writer - to an audience of which you are not a member: i.e. adults writing and publishing for children and young people.
I agree with him that in YA fiction, where the boundaries become blurred - adults frequently enjoying books written for young adults, and vice versa - it is also a problem of categorisation. I work in a charity bookshop, and quite often find books I know to be written by so-called YA authors misshelved amongst the general fiction. I tend to leave them there, especially if there's also a copy in the children's section. I believe if a book is in the right place if it is somewhere where it might be picked up and read.
But I digress. McGowan is concerned about adults missing out on
authors they might appreciate (Meg Rosoff and Patrick Ness to name but
two: amongst my favourites as well); and indeed authors missing out on
readers. But he also seems to suggest that teenagers should be writing
for teenagers, and there I'm not so sure I agree: at least, not to the
exclusion of older writers.
Like so many other things, there's a continuum. I wouldn't disagree that there are likely to be teenagers who could write highly publishable books for their own age and others, but where should it stop? 12 year-olds writing middle grade?
One thing I am sure of, no-one is going to suggest the very youngest children create their own stories. Not only is the writing and design of picture books a sophisticated skill, the very act of reading together is linked to the ancient art of storytelling: and maybe that is something that deserves to be remembered.
The old have always told stories to the young, and it has been a relationship treasured by both, for many good reasons. Let's not stop.