Perhaps we should add "for unregistered file types" there but if I am installing a software, I am probably wanting it to associate themselves for relevant files and I wouldn't want to go through settings to find all relevant files
The proper ux is peovably a "this application wants to open these file types" system pop up
Lots of applications (specifically dev-oriented ones to be fair) will have a part in the Windows Installer where you can tick a box that says something like "open .xyz with APP_GETTING_INSTALLED". Some better ones give you a list of file extensions that you'd like to open with the installing app.
Been a while since I've seen the WinRAR install screen, but pretty sure it does exactly what I described
I can see an argument for a warning if your new app is taking over a file type that an old app was handling; but if you have no app to handle it I don't see it matters much.
The reality is nobody makes ad revenue from WinRAR opening .ZIP files so nobody cares.
Perhaps we should add "for unregistered file types" there but if I am installing a software, I am probably wanting it to associate themselves for relevant files and I wouldn't want to go through settings to find all relevant files
The proper ux is peovably a "this application wants to open these file types" system pop up