User, who came from some other oses, remember they cannot remove file opened by some application. They used to guess, which application open this file and close it.
On other hand, in Linux world, you can ask system to remove file, entry in directory for this file was removed, but file persist.
Imagine case of low disk space. User decided to remove some files (such like cache, tmp, log), but no space was retrieved.
Solution: when trying to remove file, list applications, which currently opens these files and allow to close them or abort removing.
Another solution: You can also just remove file and list apps, which opens it. User can close apps, which uses (deleted?) files. System might free resources, when each of these app was closed.
The fuser command will tell you what process is using a given file. That is usually enough to identify the application, although I have sometimes needed to do “ps -auxf” then find the process and look for its parent process.
This is a brainstorm category. I know, how to do that, but user needs GUI for this.