It's not just that though, the whole app itself zooms out weird. That's the main thing *I* notice. The app very slowly shrinks then it chops and goes down into the small icon. It also stops moving very abruptly. After it stops moving abruptly, the wallpaper quits moving too.
Also the animation is screwed up when going into the app switcher. The app starts to go down (app to homescreen animation) then it jumps into the app switcher and it looks weird. The wallpaper can also be seen zooming in a weird way and then blurring into the background very strangely in the app switcher.
Also, it goes very linearly back to the position of the app icon where in the regular animation, there's a bit more of a rounding effect, it curves backward into the app where iPhone 7 devices just fly straight backward into the app.
The blur effect was on iPhone 6s devices only. Perhaps the newest iPads. The blurring effect was seen on the icons mostly and it was simply not present on older devices. Even my iPhone 6 (which handled blurring very well when I still had it) didn't have the effect. Same for my iPad mini 2. They simply dimmed the icons while they zoomed, just like how it is now. In one of the last betas of iOS 10 the blur effect on the icons during the animation was removed from ALL devices and it remains that way today.
Yeah I have noticed this too, the animation starts going extremely quick but it looks like total crap. iPhone 6s looks very smooth and natural but there is a noticeable delay from when you hit the button to when it actually starts zooming out to the homescreen. Even with the triple click accessibility shortcuts disabled.