I think I finally figured out why most of the stories (especially the new ones) don't appeal to me.
First off, I grew up with classical literature. I was figuratively born with a book in my hand. I wasn't even ten years old when I first read all of Dracula by Bram Stoker which might have given me an acquired taste for horror literature. When I was very young I spent the weeks leading up to Halloween reading horror classics. By the time I was 13 I already had a small library of about 150 books (some of which I have since sold).
As for Creepypasta itself, I knew about it before I knew it had a name. I read about Polybius in 2005, and the Tails Doll Curse in 2009 (which I found comical). I discovered Creepypasta as a whole in 2012 when I came across Yuriofwind's videos about BEN, and the Pokepastas. That lead me to discovering the wiki which was still young.
At that time the Creepypasta Wiki was still more like /x/ and even stories with heavily used cliches were good. In fact the writing was so good that cliches could be used without decreasing the quality of a story. It was rare when I found a story I didn't like, I even liked the ones that I thought had a few issues.
As the wiki began to increase in popularity quality standards unfortunately had to be raised. Creepypasta's memic status attracted a large crowd of children and teenagers, a lot of which made wikia accounts and wrote stories that were below average or straight up knock-offs. Slender Man's popularity brought Slenderpastas in by the thousands, as well as thinly disguised knock-offs. Jeff the Killer was mercilessly ripped off by children and teens who were bullied, had low self esteem, saw it as a way to make themselves an edgy character, or thought it was so good that they had to plagiarise it. JC the Hyena's Sonic.exe made a mockery of the haunted video game genre as did the spin-offs and rip-offs of it. People started copying and pasting lost episode and theory pastas and rewriting them about their favorite shows (even if it didn't fit). And video game pastas ended up being rip-offs of Ben. Though that is not to say that stories of lower standards, rip-offs, and spin-offs were banned immediately. For a time they were allowed if they were written well enough.
When I found this site in 2012 it had that nice black, gray and white theme to it as opposed to the red and gray one it has today. Spin-offs and stories that had cliches were still allowed as long as they were well written.
I think my problem is that this site isn't what it used to be. Although quality standards were raised to blacklist spin-offs, rip-offs, overly cliched stories, and stories with bad spelling and grammar, they are still pretty low. Since the quality standards were raised to where the stories on here cannot be recognized as Creepypastas anymore, I expect them to at least be an all-new kind of horror literature with professional level horror.
UPDATE 1: The site is not only suffering a decline in quality, but also copyright claims seem to be wiping out all the classics. So far Candle Cove and 1999 have been deleted over copyright claims.