[1] z-index, text overlap, mixed states, etc. These are not questionable design choices. They're bugs. And lumping them in only detracts from the site and the many legit design gripes (problems of focus, alignment, contrast, usability, etc.)
I understand what you're saying, and perhaps the name of the Tumblr should change to "Issues with iOS7", but that sounds pretty boring to me. Instead, we can all agree that sloppy/bad decision-making, sloppy QA practices, etcetera can be learned from, and that there is value in identifying (and avoiding) these mistakes both in the works of others and in our own work.
Perhaps they made it past QA/testing because what is an obvious bug in a screenshot isn't necessarily obvious to generate or replicate.
I haven't seen any of those bugs in the time I've spent in iOS7.
This is fail culture masquerading as design critique, and it isn't even doing that well.
Critique that doesn't actually tell what's wrong ... isn't.
Let's talk about the z-index issue with the AppStore icon. How is this reproduced? I have never seen that. How do I know it's not shopped?
All it says is "z-index". Not useful. Not really a critique to me, it's just too terse.
I disagree that critique must inherently describe the problem. Sometimes, the problem is fairly self descriptive, especially with what this blog provides, which is obvious issues that most of the blog's audience will immediately understand as "sloppy" - that is, I shouldn't have to explain why the z-index issue is sloppy to justify my criticism, but if you want a bug report, I can explain how I got there.
The worse thing would be if people blindly said things like "iOS7 is just not intuitive" and went on to drink their PBR and evangelize about Phonebloks - instead, these are real examples of why iOS7 could be better.
At the very least, this thread is instructive for learning designers. I know as a younger programmer and designer, when someone said that "JavaScript has the weirdest quirks", it was useless unless someone showed me the quirks. Along came Douglas Crockford's Good Parts, which, while critical of the bad parts, was very instructive. I think this can function in similar ways.
It's not just "Fail" culture rearing its stupid head - the tone is far from embarrassing to Apple, and instead is generally descriptive of legitimate design failures.