I heavily rely on Spotlight to start applications when I’m on MacOS. I generally
disable a majority of things that end up in the Spotlight index and only leave
applications as that’s the primary thing I’m wanting to be accessible when I use
spotlight via its keyboard shortcut
I recently went through the upgrade procedure to get MacOS Big Sur on one of my machines and noticed that my applications were completely missing from Spotlight. After some brief searching, I came across a stack exchange that seemed to have a solution that works. For bookmarking purposes, I’ll record the commands from that entry that worked for me (should I ever need to do it again).
The gist is basically retriggering an index by stopping and starting spotlight.
sudo mdutil -a -i off
sudo mdutil -a -i on
The other commands to load and unload Spotlight did not work on my machine as I have some Integrity Protection system that must be enabled. I don’t really have details on it, but since simply stopping and starting resolved my issue, I left it at that.
Source: Apple Stack Exchange