I need to cleanup some early development things that I did wrong, so I want a clean install. I uninstalled arduino using the uninstall.sh and removed the ~/arduino-1.8.13 directory and the ~/.ardunio15 directory.
However, after a new install without doing anything else I see that I have in board manager "ESP32 Arduino (in sketchbook) which is one of the items that I hoped I was purging.
Installation folder (looks like it was ~/arduino-1.8.13 on your computer)
Data folder (~/.arduino15)
Sketchbook folder
That leftover ESP32 boards platform installation is in the hardware subfolder of your sketchbook. The default location of the sketchbook is ~/Arduino, but you can set it to any location you like. You can find the location in the Arduino IDE's File > Preferences > Sketchbook location setting.
Thanks, found all the old and broken Hardware stuff, in the hardware directory. Once that directory was removed I see what is expected on a clean install.
However, I decided to do it right and took the nuclear option and reformated my install harddrive. Takes 15 minutes and I'm back in business.