That #reactnative#Fabric & #TurboModules migration was a big pain, especially that I had Kotlin and Swift code to migrate, so it’s a big relief to have it done. And there is lots of completely undocumented stuff I wish I knew that would made it a lot easier to migrate
If you care about backward compatibility, supporting #Fabric & #TurboModules is realistically doable only from version 0.70+ (Swift support + Kotlin fixes + CMake builds instead of NDK + autolinking for Android available only in rn cli v9 which is available in RN 0.70+)