Random Chat: YA and NA

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Step up, take a seat, make yourself at home and let’s chat!

Greetings, ladies and gentlemen!
I came across this article a few days ago while browsing facebook and it prompted me to post something I have been mulling over for ages now:

Author Claims YA Does Not Exist

It links to the following article: There Is No Such Thing as the Young Adult Novel.

I am not sure if any of you have noticed, but I don’t have YA as a book genre in my blog. Quite frankly, the notion still baffles me. I am not even sure if I fully understand it, because I have seen it defined accordingly to the characters age and also to the audience’s age. It seems that the latter prevails, or at the very least a mixture of the two.

While I can understand that it may make books easier to find, defining a book by age categories seems extremely restrictive and I have found that the same formulas get used over and over again.
Ever since the YA genre came out, I cannot seem to find, for instance, a fantasy book I enjoy. Sure, there is New Adult now as well, but I cannot seem to relate to either the writing or the topics in books classified as such. On the other hand, if I pick up a YA book I am usually faced with much of the same teenage dramas, romance and, at times, tantrums.

I thoroughly miss a solid fantasy novel with characters I can relate to and which does not necessarily include romance. Something that presents a new world, one that is unique but makes sense and utterly enthrals me in the story. I cannot seem to find that anymore and I am convinced it has gotten worse since these categories were released to public.

What do you think? Have the YA and NA categories done more good or harm to the book industry, in terms of quality of books, not marketability?
Do you find any of the points I made make sense?
Tell me everything!