I held off upgrading my OS from Mojve to Catalina, and then I simply forgot to. I did it recently, and everything worked fine.

However, my Wi-Fi simply stopped working one day. No obvious reason why either. I tried sharing my phones data connection via USB and Bluetooth, but neither worked.

A quick search led me to the solution.

macReport’s article has a suggestion that worked. I followed the instructions in the step 4 “Create a new network location” section, and low and behold Wi-Fi connectivity was restored.

Why does this work? I’ve absolutely no idea.