Reduced motion + Prefer Cross-Fade Transition produces not smooth animations on iOS

[kirillzyusko]

Describe the bug

A combination of Reduced motion and Cross-Fade Transition on iOS makes animation not smooth.

Code snippet

You can use example app.

Repo for reproducing

You can use example app.

To Reproduce
Steps to reproduce the behavior:

1. Go to "Animated Keyboard" example
2. Click on TextInput
3. See animation smoothness

Expected behavior

Animations should be smooth.

Screenshots

RPReplay_Final1724771280.MP4

Smartphone (please complete the following information):

• Desktop OS: MacOS 14.41
• Device: iPhone 11
• OS: 17.4
• RN version: 0.75.2
• RN architecture: old/new
• JS engine: Hermes
• Library version: 1.13.2

Additional context

Would be good to check how other apps are handling this. But I think the common feature would be the fact that useKeyboardHandler should give gradual values and don't change values when keyboard starts movement or finishes its movement.