Read my edit.
Seriously - you are lucky your eyes are not as sensitive as ours. You should just agree there are people like me, and many others, that can see the issues with iOS9 plain and clear. Please also realise that Apple improving iOS9 to satisfy us people who can notice these things will make YOUR experience better too.
You make it sound as if it's fine as it is, and that improving it further will someone be a bad thing...
I am telling you that at an objective level iOS9 is worse, pure facts and figures pulled right out of Xcode.
iOS9 never even caps out at 60fps scrolling, I'd typically see 50-55fps once it ramps up, but it would often start off as low as 15fps. I've no idea if this is Apple's smart move to reduce CPU usage (similar to Android's CPU governors), but it leaves much to be desired with regards to stutter - Android has similar issues with aggresive governors that use CPU stepping depending on how intense the usage it predicts will occur based on your actions.
I've also been to Apple Stores just to see whether or not it was just my phone (never been a believer than certain phones are magically laggier than others) - nope. Every single iPhone in the Apple Stores exhibits the same lags in the same areas.