MacOS 15.1, fully updated. Text replacement worked fine before upgrading, now it does not. I can add that my iPhone 12 Pro works fine using the same replacement settings.
Nope: Did'nt work. Note that I could not use these steps on my (working) iPhone, so I did it on my (not working) Mac Mini instead. BUT when I added a new phrase on the iPhone, it began to work on the Mac too! Weird, no?