/Applications/Preview.app no longer exists but is visible in Finder? I think this happened after Catalina.

sudo ls /Applications/Preview*


claims there is no such file, even though the file is perfectly visible in the Finder.

I have a script that relies on it:

function manp(){
  man -t $1 | open -f -a /Applications/Preview.app
}


which I can fix by abbreviating to open -f -a Preview but still ... where did Preview.app go?
Did you try to explore over on the following path:

/System/Applications/Preview*