On my MBP 16" (2023) Spotlight would only return results for my OneDrive folder and for Apple's core apps (Safari, Pages, etc.). It would NOT return results from files or non-Apple apps (Illustrator, Word, etc). In other forums, users have speculated that OneDrive could be at fault. One other potentially important wrinkle for my computer - it was set up using Migration Assistant, transferring files, apps, and settings from another MBP 16" (~2020). I tried all the tricks to fix Spotlight: adding/removing the drive from Settings > Siri & Spotlight indexing, and using Terminal to turn Spotlight off/on while clearing the index. Nothing worked, even after multiple tries, booting into safe mode, etc. What ultimately worked was using root to erase/recreate the Spotlight index: (1) turn on "root" access, which is not activated by default (2) Log out, then back in as root. (3) Use Terminal to turn spotlight off. [ sudo mdutil -i off / ] (4) Use Terminal to delete the .Spotlight-V100 file in System/Volumes/Data. This is a hidden file. (3) Run mdtutil commands to clear cache to be doubly sure [ sudo mdutil -E / ], then turn Spotlight back on [ sudo mdutil -i on / ] After I completed these steps, I could see immediately that Spotlight was reindexing. I let it run overnight. In the morning, still as root, I confirmed that Spotlight was working. I then logged out/back into my regular account and voila - fixed. I have not deactivated root yet to test whether logging out of Root will make the problem return. I can't imagine it would, but ... I'm going to enjoy Spotlight again for a few days before I try turnning root off. Hoping this helps others!! What a mess.