I have the same issue. I thought it might have been related to a package update I did with homebrew or CocoaPods. Still trying to find a solution
BulletButcher
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In my case I needed to update homebrew 'brew update'
Updated Ruby to a version >= 2.7.0 'brew install ruby'
Homebrew Ruby to PATH. Find the directory with 'which ruby' and replace the file names to your .zshrc or ~/.bash_profile OR ~/.bashrc file.
(export PATH="/usr/local/opt/ruby/bin:$PATH")
Reload your SHELL config 'source ~/.bash_profile'
Be sure to have the right gem 'sudo gem install cocoapods'
I used 'gem update --system 3.5.1'
Navigate to the ios/ directory and 'pod install'
Move back to the root directory then run
watchman watch-del-all
rm -rf $TMPDIR/react-*
npx react-native start --reset-cache