For those who are trying to use IINA on Mac and getting an "operation not permitted" error using this command:
ln -s /opt/homebrew/lib/libmpv.2.dylib /Applications/IINA.app/Contents/Frameworks/libmpv.2.dylib
The new libmpv.2.dylib directory is located here:
/opt/homebrew/Cellar/mpv/0.36.0/lib/libmpv.2.dylib
You can just copy and paste that libmpv.2.dylib to the "/Applications/IINA.app/Contents/Frameworks/" directory.
Tested on an M2 MacBook Air.