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If you're having issues with some of the new features make sure that reduced motion is turned off in settings-accessibility
The Reduce Motion settings is something others including myself have used on older devices to help with stuttering and lag because the newer iOS versions can have that effect on older iPhones and iPads.
Nothing in connection to how iMessages work.
It shouldn't be the case imo on a brand new iPhone 7.
How to Fix iMessage effects not working in iOS 10
Solution 1: Disable Reduce Motion
A common fix to this issue is to turn off ‘Reduce Motion’, which you may have enabled to disable parallax effect of app icons and to reduce animations. But it seems that having this enabled creates issues for iMessage effects so turning it off may fix the problem.