Hi.
In Linux I can create ~/.arduinoIDE as link to another folder, and Arduino IDE at start reads all from there, especially arduino-cli.yaml, and uses folders described there.
It means, if arduino-ide executable will read command line argument like "--config-directory=path" it will can run different configurations.
There are many reasons for it's worth to implement.
First is of course portable installation, but not only.
I, and probably most of Arduino users, have favorite boards and use them for most projects, but rarely use some "exotic" boards. The libraries grow to gigabytes, and Arduino IDE attempt to update ALL at start...
It will be good to have many configurations, one for everyday, and some for rarely use, or a few configurations for different boards to prevent interferrence of parallel projects.
Adding startup parameter is for good programmist a few minutes of work...
Regards.
Are you installing boards that you don't use?
I am a bit surprised to hear that disk space (libraries) is a big issue. Have you looked at what they use? I have a few 'exotic' boards, but don't see a disk space problem; my fairly standard 1TB SSD is only a bit more than half full, and the biggest is my Applications Support folder. The last screen grab shows all the boards, many of which I have not used in years, if at all.
Please only comment on the GitHub issue thread if you have new technical information that will assist with the resolution. General discussion and support requests are always welcome here on the Arduino Forum.
If you find these notifications annoying, you can disable them via the advanced settings.
I'll provide instructions you can follow to do that:
Press the Ctrl+Shift+P keyboard shortcut (Command+Shift+P for macOS users) to open the "Command Palette".
A menu will appear on the editor toolbar:
Select the "Preferences: Open Settings (UI)" command from the menu. ⓘ You can scroll down through the list of commands to find it or type the name in the field.
A "Settings" tab will open in the Arduino IDE main panel.
Type arduino.checkForUpdates in the "Search Settings" field of the "Settings" tab.
Uncheck the box under the "Arduino: Check For Updates" setting.
Close the Preferences tab by clicking its X icon.
If you disable the automatic update check, make sure to periodically do a manual check for newer versions of Arduino IDE and your installed boards platforms and libraries. You can check for new versions of Arduino IDE by selecting Help > Check for Arduino IDE Updates from the Arduino IDE menus. You can check for new versions of boards platforms and libraries by selecting "Updatable" from the "Type" menu in the Boards Manager and Library Manager views.
arduino-cli.yaml file IS NOT configuration folder arduinoIDE. arduino-cli.yaml file contains only piece of important informations. Rest of informations are placed in another files in configuration folder. The parameter for arduinoIDE executable must be folder path, not file path.
It is not bad that Arduino uses gigabytes of libraries if must. Bad is often updating of rarely used libraries.
The choice from update all or not update all is not choice.
Please only comment on the GitHub issue thread if you have new technical information that will assist with the resolution. General discussion and support requests are always welcome here on the Arduino Forum.