The article didn't really shock me to tell the truth. If you have the nerves, take a look at [[Professional wrestling]] and some of the articles it links to.
A commonsense-oriented notability guideline seems as necessary as it would be difficult to implement, because opposition to such a proposal can be expected from multiple directions. Some would oppose based on their fear of deletionist book burnings, others see the strain it would put on process.
I believe such a proposal could only stand a chance as part of a far reaching reform, possibly including the abandonment of AfD in its current form.
Ideas like annex.wikia.com may be one alternative way to address the issue of articles with non-encyclopedic subjects (fiction related articles in the case of annex). Nothing beyond the obvious deletion candidates would really have to be deleted. Instead, such articles could be moved to annex, awaiting relocation into a more suitable wiki.
But I expect major difficulties explaining "just why" a subject like [[Professional wrestling aerial techniques]], despite all the references in the article, isn't fit for its own Wikipedia article. Same goes for many "recent events" and fiction related pages.
On the other hand, such "outsourcing" efforts could work wonders against vandalism, much of which happens on subjects with recent news coverage. And it would probably increase the overall reputation of Wikipedia, too.
Adrian