Transform rotate style property doesn't work properly on ios

[jmartinippon]

Description

I use @react-native-community/slider and I needed to rotate the slider.

To do so I used the css property transform, and rotate. It works well on android, but not on ios.
The slider stay to it's original position.
When I change the rotate value while I'm visualizing the slider, it rotates after the automatic assets refresh. But when I leave the screen and go back to it, the slider isn't rotated anymore.

React Native Version

0.63.4, (also experienced this behavior on 0.63.3).

Infos :

System:
OS: macOS 10.15.7
CPU: (12) x64 Intel(R) Core(TM) i7-8750H CPU @ 2.20GHz
Memory: 60.75 MB / 16.00 GB
Shell: 3.2.57 - /bin/bash
Binaries:
Node: 12.19.0 - /var/folders/m1/qrp6lm356p5_802qt9vkc9tc0000gn/T/yarn--1606988176529-0.7023249601521031/node
Yarn: 1.22.10 - /var/folders/m1/qrp6lm356p5_802qt9vkc9tc0000gn/T/yarn--1606988176529-0.7023249601521031/yarn
npm: 6.14.8 - /usr/local/bin/npm
Watchman: 20200920.192359.0 - /usr/local/bin/watchman
Managers:
CocoaPods: 1.9.3 - /usr/local/bin/pod
SDKs:
iOS SDK:
Platforms: iOS 14.2, DriverKit 20.0, macOS 11.0, tvOS 14.2, watchOS 7.1
Android SDK:
API Levels: 29, 30
Build Tools: 29.0.2, 30.0.2
System Images: android-29 | Google APIs Intel x86 Atom, android-29 | Google Play Intel x86 Atom, android-30 | Google APIs Intel x86 Atom, android-30 | Google Play Intel x86 Atom
Android NDK: Not Found
IDEs:
Android Studio: 4.1 AI-201.8743.12.41.6858069
Xcode: 12.2/12B45b - /usr/bin/xcodebuild
Languages:
Java: javac 15 - /usr/bin/javac
Python: 2.7.16 - /usr/bin/python
npmPackages:
@react-native-community/cli: Not Found
react: 16.13.1 => 16.13.1
react-native: 0.63.4 => 0.63.4
react-native-macos: Not Found
npmGlobalPackages:
react-native: Not Found

Steps to reproduce

Rotate an element with transform rotate style properties.

Expected result

The rotation is working on both android and ios.

Snack, code example, screenshot, or link to a repository:

The slider :
<Slider style={styles.fontSizeSlider} minimumValue={20} maximumValue={50} minimumTrackTintColor="#FFFFFF" maximumTrackTintColor="#000000" thumbTintColor="#FFFFFF" onValueChange={handleValueChange} value={textSize} />

Associated style :
fontSizeSlider: { flexBasis: '30%', width: 200, height: 40, transform: [{ rotate: '-90deg' }], },

The slider is under a flex container wich has the following css attributes :

inputContainer: { top: '50%', display: 'flex', flexDirection: 'row', flexWrap: 'wrap', alignContent: 'center', },

[github-actions]

⚠️	Missing Environment Information
ℹ️	Your issue may be missing information about your development environment. You can obtain the missing information by running react-native info in a console.

[jmartinippon]

Infos added!

[chrisglein]

Put this in a Snack here.
Confirmed the repro: rotates on Android (and Web), doesn't on iOS.