Got burned by this when I was wanting to uninstall MS Office from my laptop recently.

Filtering with string "office" turned up nothing in the list of installed programs but it was clear that "MS Office Click-to-Run SxS" was regularly grinding away chewing lots of CPU. So I was not crazy -- Office was installed.

The names of the "installed program" for MS Office is now Microsoft 365. Brilliant value add on that one </sarc>