A couple of built-in I didn't see:

macOS software versions:

    sw_vers

macOS hardware overview:

    system_profiler SPHardwareDataType

Convert binary plist to xml

    plutil -convert xml1 -o out.xml in.plist

A couple of lesser known, but also handy ones to install:

    brew install dark-mode

    brew install duti

> screencapture - take screenshots

Big fan of screencapture. I wanted something similar but for capturing window videos, so I built https://github.com/xenodium/macosrec

I often wrap command line utilites with Emacs functions (don't need to remember invocation flags/structure but also enables batch invocations) https://xenodium.com/recordscreenshot-windows-the-lazy-way