After fiddling with MAMP and its installation of PHP as global for scripts in terminal/console for hours I gave up with the somehow logic instructions for MAMP installations, as I was unable to upgrade the laravel/installer.
https://gist.github.com/yehgdotnet/fd9b86a08c5e0c03fa57ad3ae8217892
# install dependencies
brew install autoconf # required by pecl
brew install libzip
# install zip extenion in your selected MAMP PHP version
ls /Applications/MAMP/bin/php/
cd /Applications/MAMP/bin/php/php[Version]bin
pecl install zip
# edit php.ini in your selected MAMP PHP version
ls /Applications/MAMP/conf/p*
cd /Applications/MAMP/conf/php7.3.8/
echo "extension=zip" >> php.ini
What worked for me was to install PHP on my macos with HomeBrew and link/add it to the $PATH.
https://stackoverflow.com/questions/58290566/install-ext-zip-for-mac/58300437#58300437
brew update
brew install php@7.3
echo 'export PATH="/usr/local/opt/php@7.3/bin:$PATH"' >> .bash_profile
echo 'export PATH="/usr/local/opt/php@7.3/sbin:$PATH"' >> .bash_profile