on my mac upon running pulumi up for a typescript project I got the error Library not loaded: /usr/local/opt/icu4c/lib/libicui18n.69.dylib .
Further digging I found this thread has the similar issue mentioned for a php issue node.js - dyld: Library not loaded: /usr/local/opt/icu4c/lib/libicui18n.62.dylib error running php after installing node with brew on Mac - Stack Overflow.
Solution Worked For me is :
brew reinstall icu4c