How to disable or uninstall iTunes under High Sierra without disabling SIP This answer explains how to uninstall iTunes after disabling SIP.  This appears to be a necessary step for uninstalling iTunes on versions of OSX starting with 10.13 High Sierra or earlier.

I'd prefer not to disable SIP, since the only reason I have to do so is to prevent iTunes from launching in response to various unknown stimuli.

Is there a way to prevent iTunes from starting up without needing to disable SIP?  I just want to prevent it from start up, I don't need to uninstall it.  Most importantly I want to stop it from occasionally commencing to play music for no apparent reason, but ideally I would like to prevent it from running altogether.  Is there some way I can disable it as the handler for some file type, for example?
I wasn't able to find a list of all the file types iTunes handles, but if you are willing to operate piecemeal, any time you open a file and iTunes launches, you can


Select the file in Finder
Get Info (⌘ + i)
select the app you want to use in the "Open With:" dropdown


then click "Change All..."


In the future that type of file will open in your alternate application. After a while you will have opened all the types of files you will open that iTunes handles.

Another method that you may find easier:


Right Click (or control click) the offending file in Finder
Select "Open With > Other..." (even if you see the app you want to use in the list)





Select your App (e.g. Audacity)
Check "Always Open With"

Click "Open"


It just depends on which way you find easier.