You assume a lot. My sister (who just replied to you) babysat for over a year to save up for a windows product and decided to get the iPad when it came out. I saw the whole process and she genuinely loves it — not because she is a fan girl but because it has made a huge impact on her career. I think it's a super inspiring story for artists young and old and a genuine compliment to the iPad Pro.
Our apps have been featured dozens of times and there is definitely a method to the madness. I shared my 2 cents on how to get featured as a comment on that HN link.
I would add, I think there are two steps to getting featured:
1) Make your app featurable: solves a problem in a well designed, polished way. Bonus points for showcasing one of Apple's new technologies (right now things like 3D Touch or iPad Pro optimization).
2) Get noticed by Apple: if you can make a small splash, Apple may make you a bigger one. Apple are kind of like app journalists: they are scouring the web to find out about upcoming gems or breakaway successes. I'm sure they also look at what new apps are making a splash in the charts. I think they found my first app, Grades, because I wrote a blog exploring how to build successful apps and some folks at Apple read it. You can also meet Apple folks on Twitter, conferences, and especially WWDC.
After consistently releasing apps that Apple is impressed with, they may start to build a more personal relationship with you and that's the goal.
Some people think this is all about luck but, as someone who started as a poor college student no one knew about, I found there is a method to the madness.
It isn't much better for simple animations like this but I find it much easier for complex, gesture-based, dynamic animations that can change at any time based on user input.
I'm really sorry for the site errors. It was down for about 2 hours. Never had to deal with so much traffic before and my host shut it down. Should be back up for everyone now.
They make things seem more complicated than they are.
They're often skipped.
People forget.
Folks think the screenshots are the app and try to interact with them (seriously!)
So basically, they're not a dependable way to teach stuff. On the other hand, they can definitely be helpful for quickly laying out an app's value proposition and, in some cases, can provide an important layer of instruction.
Apps like Clear purposely sacrifice discoverability for minimalism and fun. In some cases, progressive disclosure and visual cues might change the nature of the app and a walkthrough may be helpful. But Phill Ryu himself admitted that the walkthrough was a band-aid and I think we would all do well to think about how we can do better in the future.
The point is, I think there is a ton of room for innovation in the space of teaching UIs but we should keep all the chips on the table. Experiment, do user testing, but don't categorically exclude options from the table.