Can’t start applications from Spotlight
I ran the following commands (again) yesterday and they didn't seem to fix the issue

sudo mdutil -i off /
sudo rm -rf /.Spotlight-V100
sudo mdutil -i on /
sudo mdutil -E /


Then this morning macOS wanted to install some updates* and everything is back to normal now.

* a Safari update asked me to terminate "Spotlight.app" first, I found that odd because the only way to do this (to my knowledge) is through CLI or Activity Monitor